Evaluation of peripheral blood T lymphocyte surface activation markers and transcription factors in patients with early stage non-small cell lung cancer

Low Pretreatment CD4+:CD8+ T Cell Ratios and CD39+CD73+CD19+ B Cell Proportions Are Associated with Improved Relapse-Free Survival in Head and Neck Squamous Cell Carcinoma

The ectonucleotidases CD39 and CD73 are present on immune cells and play important roles in cancer progression by suppressing antitumour immunity. As such, CD39 and CD73 on peripheral blood mononuclear cells (PBMCs) are emerging as potential biomarkers to predict disease outcomes and treatment responses in cancer patients. This study aimed to examine T and B cells, including CD39 and CD73 expressing subsets, by flow cytometry in PBMCs from 28 patients with head and neck squamous cell carcinoma (HNSCC) and to assess the correlation with the treatment modality, human papillomavirus (HPV) status, and relapse-free survival (RFS). The PBMCs were examined pre-, mid-, and post-radiotherapy with concurrent cisplatin chemotherapy or anti-epidermal growth factor receptor antibody (cetuximab) therapy. Combination radiotherapy caused changes to T and B cell populations, including CD39 and CD73 expressing subsets, but no such differences were observed between concurrent chemotherapy and cetuximab. Pretreatment PBMCs from HPV+ patients contained increased proportions of CD39-CD73-CD4+ T cells and reduced proportions of CD39-/+CD73+CD4+ T cells compared to the equivalent cells from HPV- patients. Notably, the pretreatment CD4+:CD8+ T cell ratios and CD39+CD73+CD19+ B cell proportions below the respective cohort medians corresponded with an improved RFS. Collectively, this study supports the notion that CD39 and CD73 may contribute to disease outcomes in HNSCC patients and may assist as biomarkers, either alone or as part of immune signatures, in HNSCC. Further studies of CD39 and CD73 on PBMCs from larger cohorts of HNSCC patients are warranted.

Identification and validation of a novel survival prediction model based on the T-cell phenotype in the tumor immune microenvironment and peripheral blood for gastric cancer prognosis

BACKGROUND

The correlation and difference in T-cell phenotypes between peripheral blood lymphocytes (PBLs) and the tumor immune microenvironment (TIME) in patients with gastric cancer (GC) is not clear. We aimed to characterize the phenotypes of CD8⁺ T cells in tumor infiltrating lymphocytes (TILs) and PBLs in patients with different outcomes and to establish a useful survival prediction model.

METHODS

Multiplex immunofluorescence staining and flow cytometry were used to detect the expression of inhibitory molecules (IMs) and active markers (AMs) in CD8⁺TILs and PBLs, respectively. The role of these parameters in the 3-year prognosis was assessed by receiver operating characteristic analysis. Then, we divided patients into two TIME clusters (TIME-A/B) and two PBL clusters (PBL-A/B) by unsupervised hierarchical clustering based on the results of multivariate analysis, and used the Kaplan-Meier method to analyze the difference in prognosis between each group. Finally, we constructed and compared three survival prediction models based on Cox regression analysis, and further validated the efficiency and accuracy in the internal and external cohorts.

RESULTS

The percentage of PD-1⁺CD8⁺TILs, TIM-3⁺CD8⁺TILs, PD-L1⁺CD8⁺TILs, and PD-L1⁺CD8⁺PBLs and the density of PD-L1⁺CD8⁺TILs were independent risk factors, while the percentage of TIM-3⁺CD8⁺PBLs was an independent protective factor. The patients in the TIME-B group showed a worse 3-year overall survival (OS) (HR: 3.256, 95% CI 1.318-8.043, P = 0.006), with a higher density of PD-L1⁺CD8⁺TILs (P < 0.001) and percentage of PD-1⁺CD8⁺TILs (P = 0.017) and PD-L1⁺CD8⁺TILs (P < 0.001) compared to the TIME-A group. The patients in the PBL-B group showed higher positivity for PD-L1⁺CD8⁺PBLs (P = 0.042), LAG-3⁺CD8⁺PBLs (P < 0.001), TIM-3⁺CD8⁺PBLs (P = 0.003), PD-L1⁺CD4⁺PBLs (P = 0.001), and LAG-3⁺CD4⁺PBLs (P < 0.001) and poorer 3-year OS (HR: 0.124, 95% CI 0.017-0.929, P = 0.015) than those in the PBL-A group. In our three survival prediction models, Model 3, which was based on the percentage of TIM-3⁺CD8⁺PBLs, PD-L1⁺CD8⁺TILs and PD-1⁺CD8⁺TILs, showed the best sensitivity (0.950, 0.914), specificity (0.852, 0.857) and accuracy (κ = 0.787, P < 0.001; κ = 0.771, P < 0.001) in the internal and external cohorts, respectively.

CONCLUSION

We established a comprehensive and robust survival prediction model based on the T-cell phenotype in the TIME and PBLs for GC prognosis.

Mediastinal lymph node removal ameliorates cytotoxic T-lymphocyte functions in patients with non-small cell lung cancer

INTRODUCTION

Mediastinal lymph node (MLN) removal by video-assisted mediastinoscopic lymphadenectomy (VAMLA) for preoperative cancer staging was reported to be associated with increased survival. The aim of this study was to evaluate the immunologic effects of complete MLN removal by VAMLA on cytotoxic T lymphocyte (CTL) phenotype and function.

METHODS

Seventeen patients with non-small cell lung cancer (NSCLC) (stage cT1-4N0-3M0-1A) and 20 healthy participants were included in this study. Blood samples were collected before and 4 weeks after the procedure. Lymphocytes were isolated from the removed MLNs. CTL phenotypes and functions were evaluated by flow cytometry. Plasma levels of soluble programmed cell death protein 1 (sPD-1), soluble programmed cell death protein 1 ligand, and soluble CTL antigen 4 (sCTLA-4) were measured with enzyme-linked immunosorbent assay.

RESULTS

The ratio of the immunosenescent CTLs (CD3⁺CD8⁺CD28^-) was increased in peripheral blood and MLNs of the patients with NSCLC compared to controls (p = 0.037), and MLN removal did not change this ratio. PD-1 and CTL antigen 4 expressions were significantly reduced in peripheral blood CTLs after MLN removal by VAMLA (p = 0.01 and p = 0.01, respectively). Granzyme A expression was significantly reduced in the peripheral blood CTLs of the patients compared to controls (p = 0.006) and MLN removal by VAMLA significantly improved Granzyme A expression in CTLs (p = 0.003). Plasma concentrations of sPD-1 and sCTLA-4 remained unchanged after VAMLA.

CONCLUSION

CTLs in the MLNs and peripheral blood of the patients with NSCLC had an immunosenescent phenotype, increased immune checkpoint receptor expression, and impaired cytotoxicity. MLN removal by VAMLA improved these phenotypic and functional characteristics of CTLs. These changes may explain the potential contribution of VAMLA to improved survival.

Immune checkpoint blockade in glioblastoma: from tumor heterogeneity to personalized treatment

Immune checkpoint blockade (ICB) has revolutionized modern cancer therapy, arousing great interest in the neuro-oncology community. While several reports show that subsets of patients with glioma exhibit durable responses to immunotherapy, the efficacy of this treatment has not been observed for unselected patient populations, preventing its broad clinical implementation for gliomas and glioblastoma (GBM). To exploit the maximum therapeutic potential of ICB for patients with glioma, understanding the different aspects of glioma-related tumor immune responses is of critical importance. In this Review, we discuss contributing factors that distinguish subsets of patients with glioma who may benefit from ICB. Specifically, we discuss (a) the complex interaction between the tumor immune microenvironment and glioma cells as a potential influence on immunotherapy responses; (b) promising biomarkers for responses to immune checkpoint inhibitors; and (c) the potential contributions of peripheral immune cells to therapeutic responses.

A Subset of PD-1-Expressing CD56bright NK Cells Identifies Patients with Good Response to Immune Checkpoint Inhibitors in Lung Cancer

(1) Despite the effectiveness of immune checkpoint inhibitors (ICIs) in lung cancer, there is a lack of knowledge about predictive biomarkers. The objective of our study is to analyze different subsets of T-lymphocytes and natural killer (NK) cells as predictive biomarkers in a cohort of patients with nonsmall cell lung cancer (NSCLC) treated with ICI. (2) This is an observational, prospective study with 55 NSCLC patients treated with ICI. A total of 43 T and NK cell subsets are analyzed in peripheral blood, including the main markers of exhaustion, differentiation, memory, activation, and inhibition. (3) Regarding the descriptive data, Granzyme B+CD4+ Treg lymphocytes stand out (median 17.4%), and within the NK populations, most patients presented cytotoxic NK cells (CD56+CD3-CD16+GranzymeB+; median 94.8%), and about half of them have highly differentiated adaptive-like NK cells (CD56+CD3-CD16+CD57+ (mean 59.8%). A statistically significant difference was observed between the expression of PD1 within the CD56^bright NK cell subpopulation (CD56+CD3-CD16-PD-1+) (p = 0.047) and a better OS. (4) Circulating immune cell subpopulations are promising prognostic biomarkers for ICI. Pending on validation with a larger sample, here we provide an analysis of the major circulating T and NK cell subsets involved in cancer immunity, with promising results despite a small sample size.

Neo-peripheral adaptive immune score predicts neoadjuvant chemotherapy for locally advanced breast cancer

PURPOSE

Whether peripheral immune cell subsets can predict pathological complete response (pCR) in breast cancer patients remains to be elucidated. We aimed to dissect the relationship between peripheral immune cell subsets and pCR.

METHODS

Two hundred and twenty-six eligible patients from two prospective clinical trials (SHPD001 and SHPD002) in China were randomly divided into a training cohort and a validation cohort. The breast cancer subtypes in this study included hormone receptor (HR)-positive/human epidermal growth factor receptor 2 (HER2)-negative (n = 95), HER2-positive (n = 100), and triple negative (n = 31) breast cancer. We defined the "Neo-Peripheral Adaptive Immune Score" for neoadjuvant chemotherapy (neoPAI Score) based on the percentages of CD4 + T cells, CD8 + T cells, B cells, and the CD4 + /CD8 + ratio in peripheral blood. We also evaluated the ability of the neoPAI Score derived from tumor-infiltrating immune cells (TIICs) to predict survival by employing The Cancer Genome Atlas-Breast Cancer (TCGA-BRCA) database.

RESULTS

In the training cohort, multivariate analysis showed that HR status [odds ratio (OR) 0.325; 95% confidence interval (CI) 0.135-0.761; P = 0.010], HER2 status (OR 2.657; 95% CI 1.266-5.730; P = 0.011), Ki67 index (OR 3.191; 95% CI 1.509-6.956; P = 0.003), histological grade (OR 2.297; 95% CI 1.031-5.290; P = 0.045) and neoPAI Score (OR 4.451; 95% CI 1.608-13.068; P = 0.005) were independent predictors of pCR. In the validation cohort, histological grade (OR 3.779; 95% CI 3.793-1.136 × 10³; P = 0.008) and neoPAI Score (OR 90.828; 95% CI 3.827-9.843 × 10³; P = 0.019) were independent predictors of pCR. The Immune Model that integrated the neoPAI Score was more accurate in predicting pCR than the Clinical Model that exclusively contained clinicopathological parameters in both cohorts. In TCGA-BRCA database, the neoPAI Score constructed from TIICs can predict the progression-free interval (P = 0.048) of breast cancer.

CONCLUSION

The neoPAI Score defined by the percentages of peripheral immune cell subsets could be used as a potential biomarker for neoadjuvant chemotherapy efficacy.

Early change in peripheral CD4+ T cells associated with clinical outcomes of immunotherapy in gastrointestinal cancer

Biomarkers for immune checkpoint inhibitors (ICIs) are limited in gastrointestinal cancer. Peripheral blood lymphocyte subset and associated dynamic changes were retrospectively analyzed in patients with gastrointestinal cancer treated with ICIs. Cox regression and Kaplan-Meier analyses were conducted for survival. A total of 80 patients were enrolled. Baseline CD4⁺/CD8⁺ T cells were lower in patients who experienced tumor progression by 6 months than in patients who did not (1.160 ± 0.652 vs 1.705 ± 0.924, respectively; p = 0.003). In multivariate analyses, decline in CD4⁺ T cells after the first dose of ICIs (CD4-C1-decline) was an independent prognostic factor for overall survival (hazard ratio: 13.00; 95% CI: 2.24-75.54; p = 0.004). Furthermore, CD4-C1-decline was a preferable indicator for progression in patients with deficient mismatch repair/microsatellite instability-high (p = 0.027). Early change in CD4⁺ T cell counts in peripheral blood may act as a prognostic biomarker for gastrointestinal cancer patients treated with ICIs.

Intratumoral Versus Circulating Lymphoid Cells as Predictive Biomarkers in Lung Cancer Patients Treated with Immune Checkpoint Inhibitors: Is the Easiest Path the Best One?

The molecular and cell determinants that modulate immune checkpoint (ICI) efficacy in lung cancer are still not well understood. However, there is a necessity to select those patients that will most benefit from these new treatments. Recent studies suggest the presence and/or the relative balance of specific lymphoid cells in the tumor microenvironment (TEM) including the T cell (activated, memory, and regulatory) and NK cell (CD56dim/bright) subsets, and correlate with a better response to ICI. The analyses of these cell subsets in peripheral blood, as a more accessible and homogeneous sample, might facilitate clinical decisions concerning fast prediction of ICI efficacy. Despite recent studies suggesting that lymphoid circulating cells might correlate with ICI efficacy and toxicity, more analyses and investigation are required to confirm if circulating lymphoid cells are a relevant picture of the lung TME and could be instrumental as ICI response biomarkers. This short review is aimed to discuss the recent advances in this fast-growing field.

Immunophenotype of T Cells Expressing Programmed Death-1 and Cytotoxic T Cell Antigen-4 in Early Lung Cancer: Local vs. Systemic Immune Response

The overexpression of programmed death-1 (PD-1) and cytotoxic T cell antigen 4 (CTLA-4) receptors on T cells are among the major mechanisms of tumor immunoevasion. However, the expression pattern of these receptors on T cell subpopulations of a different activation status and at different sites is poorly characterized. Thus, we analyzed the expression of PD-1 and CTLA-4 on the naïve, activated, memory, and activated memory T cells. Bronchoalveolar lavage fluid (BALF) from the lung affected by lung cancer (clBALF), the opposite ‘healthy’ lung (hlBALF), and peripheral blood (PB) samples were collected from 32 patients. The cells were analyzed by multiparameter flow cytometry. The proportion of memory, activated, and activated memory CD8+ cells with the expression of PD-1 and CTLA-4 were elevated in the clBALF when compared to the hlBALF (insignificantly), but these proportions were significantly higher in the BALF when compared with the PB. The proportions of PD-1+ and CTLA-4+ T cells were elevated in the squamous cell carcinoma when compared to the adenocarcinoma patients. Also, the expression of PD-1 and CTLA-4 on T cells from the BALF was significantly higher than from PB. We report for the first time the differential expression of checkpoint molecules on CD4+ and CD8+ lymphocytes at a different stage of activation in the local environment of lung cancer. Moreover, the circulating T cells have a distinct expression of these receptors, which suggests their poor utility as biomarkers for immunotherapy.

Immune contexture defined by single cell technology for prognosis prediction and immunotherapy guidance in cancer

Tumor immune microenvironment is closely related to tumor initiation, prognosis, and response to immunotherapy. The immune landscapes, number of infiltrating immune cells, and the localization of lymphocytes in the tumor vary in across different types of tumors. The immune contexture in cancer, which is determined by the density, composition, functional state and organization of the leukocyte infiltrate of the tumor, can yield information relevant to the prediction of treatment response and patients’ prognosis. Better understanding of the immune atlas in human tumors have been achieved with the development and application of single-cell analysis technology, which has provided a reference for prognosis, and insights on new targets for immunotherapy. In this review, we summarized the different characteristics of immune contexture in cancer defined by a variety of single-cell techniques, which have enhanced our understanding on the pathophysiology of the tumor microenvironment. We believe that there are much more to be uncovered in this rapidly developing field of medicine, and they will predict the prognosis of cancer patients and guide the rational design of immunotherapies for success in cancer eradication.

Expression of PD-1 by T Cells in Malignant Glioma Patients Reflects Exhaustion and Activation

PURPOSE

Glioblastoma (GBM) is the most common primary malignant tumor in the central nervous system. Our recent preclinical work has suggested that PD-1/PD-L1 plays an important immunoregulatory role to limit effective antitumor T-cell responses induced by active immunotherapy. However, little is known about the functional role that PD-1 plays on human T lymphocytes in patients with malignant glioma.Experimental Design: In this study, we examined the immune landscape and function of PD-1 expression by T cells from tumor and peripheral blood in patients with malignant glioma.

RESULTS

We found several differences between PD-1⁺ tumor-infiltrating lymphocytes (TIL) and patient-matched PD-1⁺ peripheral blood T lymphocytes. Phenotypically, PD-1⁺ TILs exhibited higher expression of markers of activation and exhaustion than peripheral blood PD-1⁺ T cells, which instead had increased markers of memory. A comparison of the T-cell receptor variable chain populations revealed decreased diversity in T cells that expressed PD-1, regardless of the location obtained. Functionally, peripheral blood PD-1⁺ T cells had a significantly increased proliferative capacity upon activation compared with PD-1^- T cells.

CONCLUSIONS

Our evidence suggests that PD-1 expression in patients with glioma reflects chronically activated effector T cells that display hallmarks of memory and exhaustion depending on its anatomic location. The decreased diversity in PD-1⁺ T cells suggests that the PD-1-expressing population has a narrower range of cognate antigen targets compared with the PD-1 nonexpression population. This information can be used to inform how we interpret immune responses to PD-1-blocking therapies or other immunotherapies.

The Peripheral and Intratumoral Immune Cell Landscape in Cancer Patients: A Proxy for Tumor Biology and a Tool for Outcome Prediction

Functional systemic and local immunity is required for effective anti-tumor responses. In addition to an active engagement with cancer cells and tumor stroma, immune cells can be affected and are often found to be dysregulated in cancer patients. The impact of tumors on local and systemic immunity can be assessed using a variety of approaches ranging from low-dimensional analyses that are performed on large patient cohorts to multi-dimensional assays that are technically and logistically challenging and are therefore confined to a limited sample size. Many of these strategies have been established in recent years leading to exciting findings. Not only were analyses of immune cells in tumor patients able to predict the clinical course of the disease and patients' survival, numerous studies also detected changes in the immune landscape that correlated with responses to novel immunotherapies. This review will provide an overview of established and novel tools for assessing immune cells in tumor patients and will discuss exemplary studies that utilized these techniques to predict patient outcomes.

Role of tumor-infiltrating lymphocytes in patients with solid tumors: Can a drop dig a stone?

In recent years, multiple strategies for eliciting anti-tumor immunity have been developed in different clinical studies. Currently, immunotherapy was clinically validated as effective treatment option for many tumors such as melanoma, non-small cell lung cancer (NSCLC) and renal cell carcinoma (RCC). Some surface receptors of immune cells, called immune checkpoint receptors, may inhibit activity of proinflammatory lymphocytes, following binding with specific ligands. Cancer cells exploit these mechanisms to inactivate tumor-infiltrating lymphocytes (TILs) to escape from immunosurveillance. Among the different tumor-infiltrating immune cell populations, including leucocytes, macrophages, dendritic cells and mast cells, TILs are considered a selected population of T-cells with a higher specific immunological reactivity against tumor cells than the non-infiltrating lymphocytes. In this review we will discuss the promising role of TILs as biomarkers reflecting the immune response to the tumor, describing their potential ability to predict the prognosis and clinical outcome of immunotherapy in some solid tumors.