Clinical significance of regulatory T cells and CD8+ effector populations in patients with human endometrial carcinoma

Tumor immunity: A brief overview of tumor‑infiltrating immune cells and research advances into tumor‑infiltrating lymphocytes in gynecological malignancies (Review)

Tumor immunity is a promising topic in the area of cancer therapy. The 'soil' function of the tumor microenvironment (TME) for tumor growth has attracted wide attention from scientists. Tumor-infiltrating immune cells in the TME, especially the tumor-infiltrating lymphocytes (TILs), serve a key role in cancer. Firstly, relevant literature was searched in the PubMed and Web of Science databases with the following key words: 'Tumor microenvironment'; 'TME'; 'tumor-infiltrating immunity cells'; 'gynecologic malignancies'; 'the adoptive cell therapy (ACT) of TILs'; and 'TIL-ACT' (https://pubmed.ncbi.nlm.nih.gov/). According to the title and abstract of the articles, relevant items were screened out in the preliminary screening. The most relevant selected items were of two types: All kinds of tumor-infiltrating immune cells; and advanced research on TILs in gynecological malignancies. The results showed that the subsets of TILs were various and complex, while each subpopulation influenced each other and their effects on tumor prognosis were diverse. Moreover, the related research and clinical trials on TILs were mostly concentrated in melanoma and breast cancer, but relatively few focused on gynecological tumors. In conclusion, the present review summarized the biological classification of TILs and the mechanisms of their involvement in the regulation of the immune microenvironment, and subsequently analyzed the development of tumor immunotherapy for TILs. Collectively, the present review provides ideas for the current treatment dilemma of gynecological tumor immune checkpoints, such as adverse reactions, safety, personal specificity and efficacy.

Features of the immunosuppressive tumor microenvironment in endometrial cancer based on molecular subtype

Endometrial cancer (EC) is one of the three most prevalent gynecological tumors affecting women and is the most prevalent gynecological malignancy in the developed world. Its incidence is rapidly increasing worldwide, mostly affecting postmenopausal women, whereas recently its prevalence has increased in younger people. EC is an immune gene disease and many studies have shown that the tumor-immunosuppressive microenvironment plays an important role in cancer progression. In recent years, findings regarding the immunosuppressive tumor microenvironment (ITME) of EC have included immune evasion mechanisms and immunotherapy, which are mostly immune checkpoint inhibitors (ICI) for EC. Recently studies on the ITME of different molecular types of EC have found that different molecular types may have different ITME. With the research on the immune microenvironment of EC, a new immunophenotype classification based on the immune microenvironment has been carried out in recent years. However, the impact of the ITME on EC remains unclear, and the immunophenotype of EC remains limited to the research stage. Our review describes recent findings regarding the ITME features of different EC molecular types. The advent of immunotherapy has brought hope for improved efficacy and prognosis in patients with advanced or recurrent EC. The efficacy and safety of ICIs combination therapy remains the focus of future research.

The Evolving Landscape of Immunotherapy in Uterine Cancer: A Comprehensive Review

Endometrial cancer affects the uterus and is becoming increasingly common and deadly. Although surgery and adjuvant pelvic radiotherapy can often cure the disease when it is contained in the uterus, patients with metastatic or recurrent disease have limited response rates to chemotherapy, targeted agents, and hormonal therapy. To address this unmet clinical need, innovative treatment strategies are needed, and a growing focus on the immunomodulation of the tumor microenvironment has arisen. Current data suggest that active and/or passive immunotherapy may be promising for the treatment of endometrial cancer.

cfDNA Methylation Profiles and T-Cell Differentiation in Women with Endometrial Polyps

DNA methylation is a part of the regulatory mechanisms of gene expression, including chromatin remodeling and the activity of microRNAs, which are involved in the regulation of T-cell differentiation and function. However, the role of cfDNA methylation in T-cell differentiation is entirely unknown. In patients with endometrial polyps (EPs), we have found an imbalance of T-cell differentiation and an aberrant cfDNA methylation profile, respectively. In this study, we investigated the relationship between cfDNA methylation profiles and T-cell differentiation in 14 people with EPs and 27 healthy controls. We found that several differentially methylated genes (DMGs) were associated with T-cell differentiation in people with EPs (ITGA2-Naïve CD4, r = -0.560, p = 0.037; CST9-EMRA CD4, r = -0.626, p = 0.017; and ZIM2-CM CD8, r = 0.576, p = 0.031), but not in healthy controls (all p > 0.05). When we combined the patients' characteristics, we found a significant association between ITGA2 methylation and polyp diameter (r = 0.562, p = 0.036), but this effect was lost when adjusting the level of Naïve CD4 T-cells (r = 0.038, p = 0.903). Moreover, the circulating sex hormone levels were associated with T-cell differentiation (estradiol-Naïve CD4, r = -0.589, p = 0.027), and the cfDNA methylation profile (testosterone-ZIM2, r = -0.656, p = 0.011). In conclusion, this study has established a link between cfDNA methylation profiles and T-cell differentiation among people with EPs, which may contribute to the etiology of EPs. Further functional studies are warranted.

Single-Cell Sequencing of Malignant Ascites Reveals Transcriptomic Remodeling of the Tumor Microenvironment during the Progression of Epithelial Ovarian Cancer

Epithelial ovarian cancer (EOC) is the main cause of mortality among gynecological malignancies worldwide. Although patients with EOC undergo aggregate treatment, the prognosis is often poor. Peritoneal malignant ascites is a distinguishable clinical feature in EOC patients and plays a pivotal role in tumor progression and recurrence. The mechanisms of the tumor microenvironment (TME) in ascites in the regulation of tumor progression need to be explored. We comprehensively analyzed the transcriptomes of 4680 single cells from five EOC patients (three diagnostic samples and two recurrent samples) derived from Gene Expression Omnibus (GEO) databases. Batch effects between different samples were removed using an unsupervised deep embedding single-cell cluster algorithm. Subcluster analysis identified the different phenotypes of cells. The transition of a malignant cell state was confirmed using pseudotime analysis. The landscape of TME in malignant ascites was profiled during EOC progression. The transformation of epithelial cancer cells into mesenchymal cells was observed to lead to the emergence of related anti-chemotherapy and immune escape phenotypes. We found the activation of multiple biological pathways with the transition of tumor-associated macrophages and fibroblasts, and we identified the infiltration of CD4⁺CD25⁺ T regulatory cells in recurrent samples. The cell adhesion molecules mediated by integrin might be associated with the formation of the tumorsphere. Our study provides novel insights into the remodeling of the TME heterogeneity in malignant ascites during EOC progression, which provides evidence for identifying novel therapeutic targets and promotes the development of ovarian cancer treatment.

Crosstalk of Redox-Related Subtypes, Establishment of a Prognostic Model and Immune Responses in Endometrial Carcinoma

Simple Summary

In order to explore the role of redox as a prognostic indicator in endometrial carcinoma (EC), we detected the expression patterns of 55 redox-related genes (RRGs) in EC cohorts from public databases. Performing consensus cluster algorithm, we determined four molecular subclusters based on RRGs which had significant differences in overall survival (OS) and immune activities of EC patients. Furthermore, we developed a prognostic risk model on the basis of the redox-related subtype by stepwise Cox regression analyses. All EC patients were divided into high-risk and low-risk groups according to the median value of risk score. Our proposed model could accurately assess the clinical outcome and had favorable independent ability in EC cases. Moreover, our signature can serve as a predictor for immune status and chemotherapy sensitivity.

Abstract

Redox plays a central part in the pathogeneses and development of tumors. We comprehensively determined the expression patterns of redox-related genes (RRGs) in endometrial carcinoma (EC) cohorts from public databases and identified four different RRG-related clusters. The prognosis and the characteristics of TME cell infiltration of RRGcluster C patients were worse than those of other RRG clusters. When it comes to the gene cluster, there were great differences in clinicopathology traits and immunocyte infiltration. The RRG score was calculated by Cox analyses, and an RRG-based signature was developed. The risk score performed well in the EC cohort. Samples were separated into two risk subgroups with the standard of the value of the median risk score. Low-risk patients had a better prognosis and higher immunogenicity. In addition, RRG score was closely associated with immunophenoscore, microsatellite instability, tumor mutation burden, tumor stem cell index, copy number variation and chemotherapy sensitivity. The nomogram accurately predicted the prognosis of patients, and our model showed better performance than other published models. In conclusion, we built a prognostic model of RRGs which can help to evaluate clinical outcomes and guide more effective treatment.

T-cell Exhaustion in Organ Transplantation

Exhaustion of T cells occurs in response to long-term exposure to self and foreign antigens. It limits T cell capacity to proliferate and produce cytokines, leading to an impaired ability to clear chronic infections or eradicate tumors. T-cell exhaustion is associated with a specific transcriptional, epigenetic, and metabolic program and characteristic cell surface markers' expression. Recent studies have begun to elucidate the role of T-cell exhaustion in transplant. Higher levels of exhausted T cells have been associated with better graft function in kidney transplant recipients. In contrast, reinvigorating exhausted T cells by immune checkpoint blockade therapies, while promoting tumor clearance, increases the risk of acute rejection. Lymphocyte depletion and high alloantigen load have been identified as major drivers of T-cell exhaustion. This could account, at least in part, for the reduced rates of acute rejection in organ transplant recipients induced with thymoglobulin and for the pro-tolerogenic effects of a large organ such as the liver. Among the drugs that are widely used for maintenance immunosuppression, calcineurin inhibitors have a contrasting inhibitory effect on exhaustion of T cells, while the influence of mTOR inhibitors is still unclear. Harnessing or encouraging the natural processes of exhaustion may provide a novel strategy to promote graft survival and transplantation tolerance.

The landscape and prognostic value of immune characteristics in uterine corpus endometrial cancer

In the present study, we explored the clinical and immunological characteristics of 575 uterine corpus endometrial carcinoma (UCEC) samples obtained from The Cancer Genome Atlas (TCGA) using the ESTIMATE and CIBERSORT algorithms. First, Kaplan-Meier and univariate Cox regression analyses indicated that the immune cell score was a prognostic factor for overall survival (OS) and recurrence-free survival (RFS). Multivariate Cox regression analysis further revealed that the immune cell score was an independent prognostic factor for UCEC patients. Second, we investigated the correlation between the infiltration levels of 22 types of immune cells and the immune score. Survival analysis based on the 22 immune cell types showed that higher levels of regulatory T cell, activated NK cell, and follicular helper T-cell infiltration were associated with longer OS, while higher levels of CD8+ T cell and naive B-cell infiltration were associated with longer RFS. Next, we performed differential expression and prognosis analyses on 1534 immune-related genes and selected five from 14 candidate genes to construct a prognostic prediction model. The area under the receiver-operating characteristic (ROC) curve (AUC) for 3- and 5-year survival were 0.711 and 0.728, respectively. Further validation using a stage I-II subgroup showed similar results, presenting AUC values for 3- and five-year survival of 0.677 and 0.692, respectively. Taken together, the present study provides not only a deeper understanding of the relationship between UCEC and the immune landscape but also guidance for the future development of UCEC immunotherapy.

Immunotherapy and Its Development for Gynecological (Ovarian, Endometrial and Cervical) Tumors: From Immune Checkpoint Inhibitors to Chimeric Antigen Receptor (CAR)-T Cell Therapy

Gynecological tumors are malignancies with both high morbidity and mortality. To date, only a few chemotherapeutic agents have shown efficacy against these cancer types (only ovarian cancer responds to several agents, especially platinum-based combinations). Within this context, the discovery of immune checkpoint inhibitors has led to numerous clinical studies being carried out that have also demonstrated their activity in these cancer types. More recently, following the development of chimeric antigen receptor (CAR)-T cell therapy in hematological malignancies, this strategy was also tested in solid tumors, including gynecological cancers. In this article, we focus on the molecular basis of gynecological tumors that makes them potential candidates for immunotherapy. We also provide an overview of the main immunotherapy studies divided by tumor type and report on CAR technology and the studies currently underway in the area of gynecological malignancies.

The Role of Granzyme B Containing Cells in the Progression of Chronic Obstructive Pulmonary Disease

BACKGROUND

Lung inflammation plays a vital role in the pathogenesis of chronic obstructive pulmonary disease (COPD), but the characteristics of the inflammatory process remain unclear. There is growing interest in the role of granzyme B (GzmB) because CD8+ T cells can induce apoptosis of target cells by releasing GzmB, which in turn may cause tissue injury and remodeling. However, GzmB is also expressed by regulatory cells, which are able to suppress CD8+ T cell. The role of GzmB+ cells needs to be defined in COPD.

METHODS

GzmB+ and CD8+ cells on alveolar wall of surgically resected lungs of microscopically classified 12 nonsmoking control, 12 panlobular emphysema (PLE) and 30 centrilobular emphysema (CLE) subjects were localized by immunohistochemical method. Positively stained cells on alveolar wall were counted and length of corresponding alveolar wall was measured. The results were expressed as mean number of positively stained cells per mm of alveolar wall in each subject.

RESULTS

The number of GzmB+ and CD8+ cells on alveolar wall of CLE was greater than that of control or PLE subjects (p<0.05 and p<0.001, respectively). There was a positive relationship between the number of alveolar GzmB+ cells and forced expiratory volume in 1 second (FEV1) (r=0.610, p=0.003) in CLE subjects. The number of alveolar GzmB+ cells progressively decreased with decline of FEV1.

CONCLUSION

Our finding that number of alveolar GzmB+ cells was associated with FEV1 suggests that GzmB+ cells might have protective role in the progression of lung destruction and airflow limitation in CLE, which is the predominant emphysema subtype of COPD.

Senescent T cells within suppressive tumor microenvironments: emerging target for tumor immunotherapy

The functional state of the preexisting T cells in the tumor microenvironment is a key determinant for effective antitumor immunity and immunotherapy. Increasing evidence suggests that immunosenescence is an important state of T cell dysfunction that is distinct from exhaustion, a key strategy used by malignant tumors to evade immune surveillance and sustain the suppressive tumor microenvironment. Here, we discuss the phenotypic and functional characteristics of senescent T cells and their role in human cancers. We also explore the possible mechanisms and signaling pathways responsible for induction of T cell senescence by malignant tumors, and then discuss potential strategies to prevent and/or reverse senescence in tumor-specific T cells. A better understanding of these critical issues should provide novel strategies to enhance cancer immunotherapy.

Mammaglobin B may be a prognostic biomarker of uterine corpus endometrial cancer

Mammaglobin B, also referred to as secretoglobin family 2A member 1 (SCGB2A1), has been reported to be highly expressed in uterine corpus endometrial cancer (UCEC) compared with in the normal endometrium. However, the prognostic value of SCGB2A1 in UCEC remains unclear. The Oncomine, The Cancer Genome Atlas (TCGA) and Clinical Proteomic Tumor Analysis Consortium databases were used to explore the differential expression of SCGB2A1. Furthermore, data of patients with UCEC were downloaded from TCGA, and logistic regression analysis, survival analysis, univariate and multivariate analyses, and nomogram construction were performed to identify its prognostic value in UCEC. Additionally, gene set enrichment analysis (GSEA) was utilized to estimate the mechanisms of SCGB2A1 in UCEC. Finally, immune infiltration of SCGB2A1 in UCEC was analyzed using the Tumor Immune Estimation Resource. Decreased mRNA and protein expression levels of SCGB2A1 were significantly associated with poor prognostic clinicopathological characteristics (all P<0.05). Additionally, low expression levels of SCGB2A1 were associated with decreased survival of patients with UCEC compared with high expression levels of SCGB2A1. Furthermore, the independent prognostic value of SCGB2A1 in UCEC was identified by univariate and multivariate analyses. A nomogram based on 6 variables, including SCGB2A1 expression, was developed for the estimation of the 1-, 3-, and 5-year survival probability in UCEC. Additionally, GSEA suggested that the vascular endothelial growth factor, PTEN, platelet-derived growth factor, DNA repair, KRAS signaling, and PI3K-AKT-mTOR signaling pathways were differentially enriched in the low SCGB2A1 expression phenotype. Finally, high infiltration levels of CD8+ T cells were associated with SCGB2A1 in UCEC and this was associated with prognosis. The present results indicated that SCGB2A1 may be a promising independent prognostic factor in UCEC. These signaling pathways may be crucial for the regulation of UCEC via SCGB2A1.

Immune disorder in endometrial cancer: Immunosuppressive microenvironment, mechanisms of immune evasion and immunotherapy

Immunotherapy is an emerging clinical approach that has gained traction over the past decade as a novel treatment option for lung cancer and melanoma. Notably, researchers have made marked improvements in the treatment of endometrial cancer (EC), and potential immune responses have been identified in patients with EC, thereby offering the possibility of exploring immunotherapy for EC. Nevertheless, various needs remain unmet, and immunotherapy applications in EC have yielded limited success, as only a minority of patients exhibited a clinical response. Therefore, further understanding of immune dysfunction associated with EC is still required. The present review describes recent findings regarding the immunosuppressive microenvironment of EC, with emphasis on immune evasion mechanisms and immunotherapy in EC.

ATM mutations as an independent prognostic factor and potential biomarker for immune checkpoint therapy in endometrial cancer

The morbidity and mortality of endometrial cancer has been increasing over years. Ataxia telangiectasia mutated (ATM) gene, encoding a protein kinase participated in the response to DNA damage, is frequently mutated in endometrial cancer patients. However, the potential relationship between ATM mutations and the progression of endometrial cancer remains unclear. We performed an integrative bioinformatics analysis to investigate the relationship between ATM mutational status with clinical outcomes and tumor microenvironment in endometrial cancer patients. The whole exome sequencing data, RNA sequencing data and clinical information were collected from The Cancer Genome Atlas (TCGA) dataset. We found that mutation in the ATM gene was an independent prognostic factor for endometrial cancer. Antitumor immune pathways were enriched in endometrial tumors with ATM mutations. The tumor-infiltrating T lymphocytes, especially cytotoxic lymphocytes, were generally more abundant in tumors with ATM mutations. Furthermore, patients with ATM mutations exhibited higher tumor mutational burden, higher neoantigen load and increased expression levels of some immune checkpoints. In conclusion, the present study indicated that ATM mutations were linked to longer overall survival of endometrial cancer. Our findings may add better understanding for potential immunotherapy of endometrial cancer.

Characterization of CD103+ CD8+ tissue-resident T cells in esophageal squamous cell carcinoma: may be tumor reactive and resurrected by anti-PD-1 blockade

Though therapy that promotes anti-tumor response about CD8⁺ tumor-infiltrating lymphocytes (TILs) has shown great potential, clinical responses to CD8⁺ TILs immunotherapy vary considerably, largely because of different subpopulation of CD8⁺ TILs exhibiting different biological characters. To define the relationship between subpopulation of CD8⁺ TILs and the outcome of antitumor reaction, the phenotype and function of CD103⁺ CD8⁺ TILs in esophageal squamous cell carcinoma (ESCC) were investigated. CD103⁺ CD8⁺ TILs were presented in ESCC, which displayed phenotype of tissue-resident memory T cells and exhibited high expression of immune checkpoints (PD-1, TIM-3). CD103⁺ CD8⁺ TILs were positively associated with the overall survivals of ESCC patients. This population of cells elicited potent proliferation and cytotoxic cytokine secretion potential. In addition, CD103⁺ CD8⁺ TILs were elicited potent anti-tumor immunity after anti-PD-1 blockade and were not affected by chemotherapy. This study emphasized the feature of CD103⁺ CD8⁺ TILs in immune response and identified potentially new targets in ESCC patients.

Identification of prognostic immune-related genes in the tumor microenvironment of endometrial cancer

Endometrial cancer (EC) is one of the most common gynecologic malignancies. To identify potential prognostic biomarkers for EC, we analyzed the relationship between the EC tumor microenvironment and gene expression profiles. Using the ESTIMATE R tool, we found that immune and stromal scores correlated with clinical data and the prognosis of EC patients. Based on the immune and stromal scores, 387 intersection differentially expressed genes were identified. Eight immune-related genes were then identified using two machine learning algorithms. Functional enrichment analysis revealed that these genes were mainly associated with T cell activation and response. Kaplan-Meier survival analysis showed that expression of TMEM150B, CACNA2D2, TRPM5, NOL4, CTSW, and SIGLEC1 significantly correlated with overall survival times of EC patients. In addition, using the TIMER algorithm, we found that expression of TMEM150B, SIGLEC1, and CTSW correlated positively with the tumor infiltration levels of B cells, CD8+ T cells, CD4+ T cells, macrophages, and dendritic cells. These findings indicate that the composition of the tumor microenvironment affects the clinical outcomes of EC patients, and suggests that it may provide a basis for development of novel prognostic biomarkers and immunotherapies for EC patients.

Circulating Transcripts and Biomarkers in Uterine Tumors: Is There a Predictive Role?

PURPOSE OF REVIEW

Uterine cancer comprises endometrial carcinoma and the uterine sarcoma. Endometrial carcinomas are the most frequent variant and have early symptoms and a solid diagnostic work up, resulting in a rather fair prognosis. However, in case of advanced stage disease and relapse, treatment options are limited and prognosis is impaired. Uterine sarcomas are rare, often lacking symptoms and no diagnostic tool for correct pre-operative diagnosis are available. Prognosis is poor.

RECENT FINDINGS

Circulating biomarkers as a liquid biopsy could be beneficial as a diagnostic tool in uterine sarcomas. For both carcinomas and sarcomas, circulating biomarkers could be of use in predicting early disease recurrence. This review in endometrial carcinoma and uterine sarcoma focus on circulating biomarkers; such as proteins; circulating tumor cells; circulating tumor DNA; microRNA; and immune cells.

Exhaustion and senescence: two crucial dysfunctional states of T cells in the tumor microenvironment

The failure of a massive influx of tumor-infiltrating T lymphocytes to eradicate tumor cells in the tumor microenvironment is mainly due to the dysfunction of T cells hyporesponsive to tumors. T-cell exhaustion and senescence induced by malignant tumors are two important dysfunctional states that coexist in cancer patients, hindering effective antitumor immunity and immunotherapy and sustaining the suppressive tumor microenvironment. Although exhausted and senescent T cells share a similar dysfunctional role in antitumor immunity, they are distinctly different in terms of generation, development, and metabolic and molecular regulation during tumor progression. Here, we discuss the unique phenotypic and functional characteristics of these two types of dysfunctional T cells and their roles in tumor development and progression. In addition, we further discuss the potential molecular and metabolic signaling pathways responsible for the control of T-cell exhaustion and senescence in the suppressive tumor microenvironment. Understanding these critical and fundamental features should facilitate rethinking the unresponsiveness to current immunotherapies in clinical patients and lead to further development of novel and effective strategies that target different types of dysfunctional T cells to enhance cancer immunotherapy.

Increased frequency of regulatory T cells in the peripheral blood of patients with endometrioid adenocarcinoma

The aim of the present study was to investigate the frequency of cluster of differentiation (CD)4⁺CD25⁺CD127^- regulatory T cells (Tregs) in the peripheral blood mononuclear cells (PBMCs) of patients with endometrioid adenocarcinoma (EA). A total of 82 female patients with EA were recruited. The PBMCs were flow cytometrically analyzed to determine the percentage of CD4⁺CD25⁺CD127^- Tregs within the CD4⁺ T cell population. The associations between the prevalence of Tregs in PBMCs and defined clinical prognostic parameters were evaluated. To study the immunoregulatory capacity of Tregs, the level of specific cytokines were detected by ELISA, and the proliferation of cells was analyzed by incorporation of ³H-thymidine. It was revealed that Treg/CD4⁺ ratio in the peripheral blood of patients with EA was 4.89±1.42%, significantly higher than Treg/CD4⁺ ratio in healthy women. No correlation was observed between Treg frequency and stage, grade of differentiation, menopausal status or age. CD4⁺CD25⁺CD127^- Tregs secreted large amounts of IL-10 but not IFN-γ. The level of IL-10 secreted by Tregs from patients with EA and healthy controls was not significantly different. In addition, there was no significant difference in the suppressive activity of Tregs in patients with EA compared with that of the healthy controls. These findings demonstrate that the increased frequency of immunosuppressive Tregs in patients with EA may be responsible for immune tolerance in endometrial cancer.

The role of biomarkers in endometrial cancer and hyperplasia: a literature review

INTRODUCTION

Endometrial cancer is the most common gynaecological cancer and its incidence is rising due to increasing obesity rates. We are also seeing an increasing trend of young women diagnosed with either endometrial cancer or its precancerous state, endometrial hyperplasia. Diagnosis is dependent on invasive testing and there is no screening tool available for either general or high-risk population groups. Whilst vast amounts of research have been undertaken in higher-profile cancers such as ovarian and cervical, endometrial cancer is comparatively less investigated.

AIM

In this literature review, we summarise the existing literature in understanding the role of tumour biomarkers for endometrial cancer and its preceding condition of endometrial hyperplasia.

METHOD

NICE Healthcare Databases Search tool was used to search Embase, Medline and PubMed databases for relevant articles.

CONCLUSION

There is currently no routinely used biomarker in endometrial cancer for diagnostic or prognostic purposes. Given the establishment of new genomic classifications of endometrial cancers, the use of biomarkers to drive therapeutic approaches will be the cornerstone for individualised cancer care in the coming decades.

Checkpoint inhibitors in endometrial cancer: preclinical rationale and clinical activity

CONTEXT

Treatment of advanced and recurrent endometrial cancer (EC) is still an unmet need for oncologists and gynecologic oncologists. The Cancer Genome Atlas Research Network (TCGA) recently provided a new genomic classification, dividing EC in four subgroups. Two types of EC, the polymerase epsilon (POLE)-ultra-mutated and the microsatellite instability-hyper-mutated (MSI-H), are characterized by a high mutation rate providing the rationale for a potential activity of checkpoint inhibitors.

MATERIALS AND METHODS

We analyzed all available evidence supporting the role of tumor microenvironment (TME) in EC development and the therapeutic implications offered by immune checkpoint inhibitors in this setting. We performed a review on Pubmed with Mesh keywords 'endometrial cancer' and the name of each checkpoint inhibitor discussed in the article. The same search was operated on clinicaltrial.gov to identify ongoing clinical trials exploring PD-1/PD-L1 and CTLA-4 axis in EC, particularly focusing on POLE-ultra-muted and MSI-H cancer types.

RESULTS

POLE-ultra-mutated and MSI-H ECs showed an active TME expressing high number of neo-antigens and an elevated amount of tumor infiltrating lymphocytes (TILs). Preliminary results from a phase-1 clinical trial (KEYNOTE-028) demonstrated antitumor activity of Pembrolizumab in EC. Moreover, both Pembrolizumab and Nivolumab reported durable clinical responses in POLE-ultra-mutated patients.

CONCLUSIONS

Immune checkpoint inhibitors are an attractive option in POLE-ultra-mutated and MSI-H ECs. Future investigations in these subgroups include combinations of checkpoints inhibitors with chemotherapy and small tyrosine kinase inhibitors (TKIs) to enhance a more robust intra-tumoral immune response.

Moving forward with actionable therapeutic targets and opportunities in endometrial cancer: NCI clinical trials planning meeting report on identifying key genes and molecular pathways for targeted endometrial cancer trials

The incidence and mortality rates from endometrial cancer are increasing. There have been no new drugs approved for the treatment of endometrial cancer in decades. The National Cancer Institute, Gynecologic Cancer Steering Committee identified the integration of molecular and/or histologic stratification into endometrial cancer management as a top strategic priority. Based on this, they convened a group of experts to review the molecular data in this disease. Here we report on the actionable opportunities and therapeutic directions identified for incorporation into future clinical trials.

Emerging targets in cancer immunotherapy

The first generation of immune checkpoint inhibitors (anti-CTLA-4 and anti-PD-1/PD-L1) targeted natural immune homeostasis pathways, co-opted by cancers, to drive anti-tumor immune responses. These agents led to unprecedented results in patients with previously incurable metastatic disease and may become first-line therapies for some advanced cancers. However, these agents are efficacious in only a minority of patients. Newer strategies are becoming available that target additional immunomodulatory mechanisms to activate patients' own anti-tumor immune responses. Herein, we present a succinct summary of emerging immune targets with reported pre-clinical efficacy that have progressed to active investigation in clinical trials. These emerging targets include co-inhibitory and co-stimulatory markers of the innate and adaptive immune system. In this review, we discuss: 1) T lymphocyte markers: Lymphocyte Activation Gene 3 [LAG-3], T-cell Immunoglobulin- and Mucin-domain-containing molecule 3 [TIM-3], V-domain containing Ig Suppressor of T cell Activation [VISTA], T cell ImmunoGlobulin and ITIM domain [TIGIT], B7-H3, Inducible T-cell Co-stimulator [ICOS/ICOS-L], CD27/CD70, and Glucocorticoid-Induced TNF Receptor [GITR]; 2) macrophage markers: CD47/Signal-Regulatory Protein alpha [SIRPα] and Indoleamine-2,3-Dioxygenase [IDO]; and 3) natural killer cell markers: CD94/NKG2A and the Killer Immunoglobulin-like receptor [KIR] family. Finally, we briefly highlight combination strategies and potential biomarkers of response and resistance to these cancer immunotherapies.

Impact of the immune cell population in peripheral blood on response and survival in patients receiving neoadjuvant chemotherapy for advanced gastric cancer

We aimed to investigate the prognostic value of the immune cells population in peripheral blood from patients with advanced gastric cancer treated with neoadjuvant chemotherapy. A total of 105 patients with advanced gastric cancer were evaluated in this study. Blood samples were collected before and 1 week after the last dose of chemotherapy. The percentage of CD3+, CD3+CD4+, CD3+CD8+, and CD4+CD25+Foxp3+ T cells was assessed using flow cytometry analysis. The relationship between T cell subsets and clinical outcome was evaluated. The percentage of CD3+CD8+ lymphocytes was significantly increased after chemotherapy and CD4+CD25+Foxp3+ regulatory T cells (Tregs) decreased ( p = 0.003 and p < 0.001, respectively). The percentage of CD3+CD8+ lymphocytes and Tregs was strongly associated with response to chemotherapy ( p = 0.017 and p < 0.030, respectively). Patients with high CD3+CD8+ T cells and low CD4+CD25+Foxp3+ Tregs had significantly increased overall survival ( p = 0.012 and p = 0.048, respectively). Neither CD3+ nor CD3+CD4+ T cells showed significant changes after chemotherapy or correlations with the clinical outcome. The positive correlation between a high CD3+CD8+ T cells or low CD4+CD25+Foxp3+ Tregs and clinical outcome indicates its key role in the prognosis of gastric cancer patients and may serve as a biomarker to identify patients likely to benefit from neoadjuvant chemotherapy.

Regulatory T Cells Suppress Natural Killer Cell Immunity in Patients With Human Cervical Carcinoma

OBJECTIVE

To determine the functional attributes of CD4 CD25 regulatory T (Treg) cells by suppressing natural killer (NK) cell activity in human cervical cancer (CC).

METHODS

Triple-color flow cytometry was used to study the phenotypic expression of CD4 CD25 Treg cells and NK cells in the peripheral blood lymphocytes (PBLs) and tumor-infiltrating lymphocytes (TILs). In vitro coculture assays were performed to illustrate the cytokine immunoregulations between Treg cells and NK cells.

RESULTS

Significantly lower expression ratio of NK cells and higher expression ratio of Treg cells in TILs than PBLs were found. The NK cells displayed significantly higher expression ratio of inhibitory NK receptors (CD158a, CD158b, and NKG2A) and lower expression ratio of activating NK receptors (NKG2D, NKp46, and NKp30) as well as perforin in TILs than PBLs, suggesting the suppressed cytotoxicity of the NK cells in the CC tumor milieu. The expression ratio of transforming growth factor-β1 (TGF-β1) on Treg cells as well as TGF-βRII on Treg cells and NK cells was significantly higher in TILs than PBLs. Further functional in vitro assays demonstrated that NK cell function was suppressed by Treg cells, mimicking the inhibition of TGF-β on NK cells, and interleukin-2/interleukin-15 stimulation was able to restore the NK cell activity.

CONCLUSIONS

These findings indicate that Treg cells in TILs may abrogate NK cell cytotoxicity through TGF-β pathway, and therefore, Treg cell elimination may enhance NK cell activity and be a novel therapeutic strategy for CC.

CD8 down-regulation on cytotoxic T lymphocytes of patients with endometrioid endometrial carcinomas

Carcinogenesis is a multistep process in which cancer cells and tumor stroma cells play important roles. T lymphocytes are immune constituents of tumor stroma and play a crucial function in anti-tumor response. By immunohistochemistry and flow cytometry, we studied T cytotoxic (CTLs) and T helper lymphocyte distribution and percentage in the tumor microenvironment and peripheral blood from 35 patients with endometrioid endometrial carcinomas (EEC). We also studied 23 healthy donors' blood samples as a control group. Tumor and non-tumoral endometrium samples were obtained. Immunohistochemistry revealed a high number of CTLs and T helper lymphocytes in the tumor stroma of myoinvasive EECs. T lymphocytes were mostly located in the invasive front. By flow cytometry, the percentages of CTLs and T helper lymphocytes were significantly higher in the tumor compared with the non-neoplastic endometrium (P = .0492 and P = .002). The mean fluorescence intensity of CD8 staining was lower in the tumor compared to the non-neoplastic endometrium (P = .001). There was also reduction of the mean fluorescence intensity of CD8 staining on peripheral blood from patients with grade 3 EECs compare to the peripheral blood from healthy donors (P = .0093). No alterations in the expression of granzymes A and B were found in the CTLs from the EEC cases. Finally, in a proteome profiler cytokine array we found that the growth differentiation factor 15 (GDF15) increased in blood in parallel to the tumor grade. EECs are capable of down-regulating CD8 expression of CTLs. Most likely, this effect is mediated by a soluble molecule present in plasma and is not a result of anergy or exhaustion state.

Genetic variation in the immunosuppression pathway genes and breast cancer susceptibility: a pooled analysis of 42,510 cases and 40,577 controls from the Breast Cancer Association Consortium

Immunosuppression plays a pivotal role in assisting tumors to evade immune destruction and promoting tumor development. We hypothesized that genetic variation in the immunosuppression pathway genes may be implicated in breast cancer tumorigenesis. We included 42,510 female breast cancer cases and 40,577 controls of European ancestry from 37 studies in the Breast Cancer Association Consortium (2015) with available genotype data for 3595 single nucleotide polymorphisms (SNPs) in 133 candidate genes. Associations between genotyped SNPs and overall breast cancer risk, and secondarily according to estrogen receptor (ER) status, were assessed using multiple logistic regression models. Gene-level associations were assessed based on principal component analysis. Gene expression analyses were conducted using RNA sequencing level 3 data from The Cancer Genome Atlas for 989 breast tumor samples and 113 matched normal tissue samples. SNP rs1905339 (A>G) in the STAT3 region was associated with an increased breast cancer risk (per allele odds ratio 1.05, 95 % confidence interval 1.03-1.08; p value = 1.4 × 10(-6)). The association did not differ significantly by ER status. On the gene level, in addition to TGFBR2 and CCND1, IL5 and GM-CSF showed the strongest associations with overall breast cancer risk (p value = 1.0 × 10(-3) and 7.0 × 10(-3), respectively). Furthermore, STAT3 and IL5 but not GM-CSF were differentially expressed between breast tumor tissue and normal tissue (p value = 2.5 × 10(-3), 4.5 × 10(-4) and 0.63, respectively). Our data provide evidence that the immunosuppression pathway genes STAT3, IL5, and GM-CSF may be novel susceptibility loci for breast cancer in women of European ancestry.

Immunotherapy in endometrial cancer - an evolving therapeutic paradigm

Endometrial cancer is the only gynecologic malignancy with a rising incidence and mortality. While cure is routinely achieved with surgery alone or in combination with adjuvant pelvic radiotherapy when disease is confined to the uterus, patients with metastatic or recurrent disease exhibit limited response rates to cytotoxic chemotherapy, targeted agents, or hormonal therapy. Given the unmet clinical need in this patient population, exploration of novel therapeutic approaches is warranted, and attention is turning to immunomodulation of the tumor microenvironment. Existing evidence suggests that endometrial cancer is sufficiently immunogenic to be a reasonable candidate for active and/or passive immunotherapy. In this review, we critically examine what is known about the microenvironment in endometrial cancer and what has been learned from preliminary immunotherapy trials that enrolled endometrial cancer patients, encouraging further attempts at immunomodulation in the treatment of aggressive forms of this disease.

Perforin, CD28 and CD95 expression in circulating CD4 and CD8 cells as predictors of head and neck (H&N) cancer patient survival

Long-term survival of H&N cancer patients has not improved significantly over the last 30 years. The possibility of using circulating blood cell phenotypes as a prognostic biomarker of H&N cancer patient was investigated in this study. Pre-treatment, circulating T lymphocyte subpopulations as well as the survival time of the patients in question were studied. Upregulated CD4+ perforin+ and CD8+ CD95+ but downregulated CD4+ CD28+ (p < 0.001) were detected in H&N cancer patients. With 3 years of follow-up time, an increase in the frequency of the pre-treatment, circulating CD4+ perforin+ cells and CD8+ perforin+ cells was showed to have reverse effects on the survival time in H&N cancer patients (p < 0.01). Detection of perforin+ frequency in CD4+ and CD8+ lymphocyte by FACS is fast, simple and cost-effective. A potential role of perforin expression in CD4+ and CD8+ cells as a prognostic biomarker for H&N cancer patient in the clinical setting was suggested.

Changes in the immune cell population and cell proliferation in peripheral blood after gemcitabine-based chemotherapy for pancreatic cancer

PURPOSE

Regulatory T cells (Tregs) play a role in the immunosuppressive state in pancreatic cancer patients. We aimed to evaluate the changes of immune cells population including Tregs caused by gemcitabine (GEM)-based chemotherapy.

METHODS

Fifty-three patients with pancreatic cancer were enrolled in this study, of which 32 received GEM- based chemotherapy. Blood samples were collected before and at least 2 weeks after the last dose of chemotherapy. The peripheral blood mononuclear cells (PBMCs) were subjected to flow cytometry analysis after labeling with anti-CD4, anti-CD25, and anti-Foxp3 antibodies. Other lymphocytes and NK cell markers were also measured. The proliferative capacity of PBMCs stimulated with anti-CD3 was analyzed using H(3) thymidine.

RESULTS

The percentage and number of Tregs were significantly decreased after chemotherapy (p = 0.032, p = 0.003, respectively). The other immune cells and the proliferative capacity did not change.

CONCLUSION

This study showed that GEM-based chemotherapy produced an immunomodulatory effect via the depletion of Tregs.

Tumor-infiltrating lymphocytes, tumor characteristics, and recurrence in patients with early breast cancer

BACKGROUND

The balance in the immune system between immune surveillance against non-self-antigens and tolerance of self-antigens is known to be associated with the prognosis of breast cancer patients. However, immunologic signals in tumor microenvironment according to biological characteristics of cancer cells have not been clearly elucidated. CD4(+) T cells, CD8(+) T cells, and forkhead box P3-positive (Foxp3) regulatory T cells (Tregs) are the main keys for immune surveillance and tolerance, respectively. We evaluated the correlations between the immunologic balance and tumor characteristics and their impact on recurrence.

PATIENTS AND METHODS

CD8(+) T cells and Foxp3(+) Tregs were detected by immunohistochemistry using the paraffin-embedded tumor samples from the 72 patients with early stage (I to III) breast cancer. Clinicopathologic data including tumor size and grade, lymph node metastasis, stage, patient's age, expression status of estrogen receptor (ER), progesterone receptor, p53, Ki-67, and human epidermal growth factor receptor-2/neu, and recurrence were reviewed.

RESULTS

The decreased number of CD8(+) T cells was significantly associated with tumors with lymph node metastasis (P=0.027), higher stage (stage III, P=0.013), and immunopositivity of Ki-67 (P=0.026). In contrast, the increased number of Foxp3(+) Tregs was significantly correlated with tumors with lymph node metastasis (P=0.027), immunopositivity for p53 (P=0.026), and positive for Ki-67 (P<0.001). There were significant correlations between the increased Foxp3(+) Treg/CD4(+) T-cell ratio and lymph node metastasis (P=0.011), the expression of ER (P=0.023), and immunopositivity of p53 (P=0.031) and Ki-67 (P= 0.003). Of note, lower Foxp3(+) Treg/CD4(+) T-cell ratio was significantly associated with triple-negative breast cancer (P=0.004). Disease-free survival of analyzed patients was significantly associated with the number of Foxp3(+) Tregs (dichotomized by a cutoff point of 17, P= 0.014) only. Univariate analysis indicated that tumor grade (P=0.017), the expression of ER (P=0.032), and non-triple-negative breast cancer (P=0.022) were independent prognostic factors for disease-free survival.

CONCLUSIONS

Our data showed that lymph node metastases, immunopositivity of p53 and Ki67, and non-triple-negative tumors were associated with high regulatory T-cell infiltration. The role of immunologic balance as a prognostic marker for recurrence must be evaluated more clearly in the future study.

Higher frequencies of GARP(+)CTLA-4(+)Foxp3(+) T regulatory cells and myeloid-derived suppressor cells in hepatocellular carcinoma patients are associated with impaired T-cell functionality

The extent to which T-cell-mediated immune surveillance is impaired in human cancer remains a question of major importance, given its potential impact on the development of generalized treatments of advanced disease where the highest degree of heterogeneity exists. Here, we report the first global analysis of immune dysfunction in patients with advanced hepatocellular carcinoma (HCC). Using multi-parameter fluorescence-activated cell sorting analysis, we quantified the cumulative frequency of regulatory T cells (Treg), exhausted CD4(+) helper T cells, and myeloid-derived suppressor cells (MDSC) to gain concurrent views on the overall level of immune dysfunction in these inoperable patients. We documented augmented numbers of Tregs, MDSC, PD-1(+)-exhausted T cells, and increased levels of immunosuppressive cytokines in patients with HCC, compared with normal controls, revealing a network of potential mechanisms of immune dysregulation in patients with HCC. In dampening T-cell-mediated antitumor immunity, we hypothesized that these processes may facilitate HCC progression and thwart the efficacy of immunotherapeutic interventions. In testing this hypothesis, we showed that combined regimens to deplete Tregs, MDSC, and PD-1(+) T cells in patients with advanced HCC restored production of granzyme B by CD8(+) T cells, reaching levels observed in normal controls and also modestly increased the number of IFN-γ producing CD4(+) T cells. These clinical findings encourage efforts to restore T-cell function in patients with advanced stage disease by highlighting combined approaches to deplete endogenous suppressor cell populations that can also expand effector T-cell populations.

Immunofluorescence-Detected Infiltration of CD4+FOXP3+ Regulatory T Cells is Relevant to the Prognosis of Patients With Endometrial Cancer

Objective

Host antitumor immune responses are associated with many types of immune cells and soluble components. In particular, CD8+ cytotoxic T lymphocytes (CTLs) play a central role. Regulatory T cells (Tregs) have been reported to induce tumor immune tolerance in various cancers. In the present study, we evaluated lymphocytic infiltration in endometrial cancer tissue to clarify its relationship with clinicopathological factors and the prognosis of patients.

Methods

The study included 53 patients whose condition was diagnosed as endometrial cancer between 1994 and 2004 at Keio University hospital. Using formalin-fixed, paraffin-embedded specimens of the uterus, immunohistochemistry was performed with antihuman CD8, antihuman CD4, and antihuman FOXP3 primary antibodies, and the binding sites of the antibodies were visualized using fluorescence-conjugate secondary antibodies. CD4+FOXP3+ cells were identified as Tregs in this study. The numbers of CD8+ cells, CD4+ cells, and Tregs as well as the Treg/CD8+ and Treg/CD4+ ratios were analyzed to evaluate the relationship between clinicopathological factors and patient prognosis.

Results

Of the 53 patients studied, 50.9% of them had early-stage disease, 49.1% had advanced stage disease, 47.2% had well-differentiated cancer (grade [G] 1), 24.5% had moderately differentiated cancer (G2), and 28.3% had poorly differentiated cancer (G3). The CD8+ and CD4+ cell counts, Treg count, and Treg/CD8+ and Treg/CD4+ ratios were significantly higher in the patients with advanced poorly differentiated carcinomas and with positive lymphovascular space invasion than in those with early well-differentiated carcinomas and with negative lymphovascular space invasion. In disease-free survival, the prognosis of the patients with high Treg counts and Treg/CD8+ ratios was significantly worse than that of the patients with low Treg counts and Treg/CD8+ ratios (P < 0.05).

Conclusions

The Treg count and Treg/CD8+ ratio may be new prognostic factors for endometrial cancer.

The aging immune system and its relationship with cancer

The incidence of most common cancers increases with age. This occurs in association with, and is possibly caused by a decline in immune function, termed immune senescence. Although the size of the T-cell compartment is quantitatively maintained into older age, several deleterious changes (including significant changes to T-cell subsets) occur over time that significantly impair immunity. This article highlights some of the recent findings regarding the aging immune system, with an emphasis on the T-cell compartment and its role in cancer.