Immunosuppressive Tumor Microenvironment Status and Histological Grading of Endometrial Carcinoma

VISTA/CTLA4/PD1 coexpression on tumor cells confers a favorable immune microenvironment and better prognosis in high-grade serous ovarian carcinoma

Introduction

Immunotherapy by blocking immune checkpoints programmed death/ligand (PD1/PDL1) and cytotoxic T-lymphocyte-associated protein 4(CTLA4) has emerged as new therapeutic targets in cancer. However, their efficacy has been limited due to resistance. A new- checkpoint V-domain Ig-containing suppressor of T cell activation (VISTA) has appeared, but the use of its inhibition effect in combination with antibodies targeting PDL1/PD1and CTLA4 has not been reported in ovarian cancer.

Methods

In this study, we investigated the expressions of VISTA, CTLA4, and PDL1 using immunohistochemistry (IHC)on 135 Formalin-Fixed Paraffin-Embedded (FFPE)tissue samples of High-grade serous carcinoma (HGSOC). VISTA, CTLA4, PDL1, PD1, CD8, CD4, and FOXP3 mRNA extracted from 429 patients with ovarian cancer in the Cancer Genome Atlas (TCGA) database was included as a validation cohort. Correlations between these checkpoints, tumor-infiltrating- lymphocytes (TILs), and survival were analyzed.

Results and discussion

CTLA4 was detectable in 87.3% of samples, VISTA in 64.7%, PD1 in 56.7%, and PDL1 in 48.1%. PDL1 was the only tested protein associated with an advanced stage (p=0.05). VISTA was associated with PDL1, PD1, and CTLA4 expressions (p=0.005, p=0.001, p=0.008, respectively), consistent with mRNA level analysis from the TCGA database. Univariate analyses showed only VISTA expression (p=0.04) correlated with overall survival (OS). Multivariate analyses showed that VISTA expression (p=0.01) and the coexpression of VISTA+/CTLA4+/PD1+ (p=0.05) were associated with better OS independently of the clinicopathological features. Kaplan-Meier analysis showed that the coexpression of the VISTA+/CTLA4+/PDL1+ and VISTA+/CTLA4+/PD1+ checkpoints on tumor cells (TCs)were associated with OS (p=0.02 and p<0.001; respectively). VISTA+/CTLA4+/PD1+ in TCs and CD4+/CD8+TILswere associated with better 2-yer OS. This correlation may refer to the role of VISTA as a receptor in the TCs and not in the immune cells. Thus, targeting combination therapy blocking VISTA, CTLA4, and PD1 could be a novel and attractive strategy for HGSOC treatment, considering the ambivalent role of VISTA in the HGSOC tumor cells.

PD-L1 Immunohistochemical Expression in Endometrial Carcinoma: Egyptian Cross-Sectional Study

OBJECTIVE

Endometrial carcinoma (EC) is the most common cancer of the female genital tract. According to the recently evolved strategies of cancer immunotherapy, immune checkpoints inhibitors are one of the most crucial strategies. Programmed Death Ligand 1 (PD-L1) is an important immune checkpoint regulator. PD-L1 antibodies have shown efficacy in clinical trials of some malignancies. Some of these antibodies have been approved for clinical usage by the Food and Drug Administration (FDA).

METHODS

This retrospective study included a total of 100 ECs, collected from archived, formalin-fixed, paraffin-embedded tissue blocks of hysterectomy specimens of Egyptian females. The samples were immunohistochemically analyzed for PD-L1 expression (in both tumor cells; TCs and tumor infiltrating leucocytes; TILs) by a semiquantitative score (0 to 4), with cutoff points of (0: <1% of the cells, 1: 1% to 4%, 2: 5% to 9%, 3: 10% to 49%, and 4: ≥ 50%). Membranous staining only was considered positive.

RESULTS

PD-L1 was highly expressed in ECs (67% TCs+ and 61% TILs+), with statistically significant relationships with age, lympho-vascular space invasion (LVSI) and TILs score (P = 0.006, 0.016 and <0.005 respectively).  However, no statistically significant relationships were detected between PD-L1 expression and the following parameters: histological type, histological grade, pathological stage (pT) or FIGO stage, myometrial, cervical, adnexal/serosal, parametrial involvements and nodal metastasis, as well as ESMO risk stratification system. Moreover, statistically significant relationships were achieved when correlating TILs score with tumor grade and LVSI (P = 0.034 and 0.012 respectively). Also, comparing endometrial hyperplasia (EH) PD-L1 and TCs PDL1 median scores achieved statistically significant relationship (P = 0.001).

CONCLUSION

Our results concluded that PD-L1 expression was greater in both TCs and TILs in a subgroup of patients that have advanced age, LVSI and are TILs-rich, identifying them as potential candidates for anti-PD-1/PD-L1 immunotherapy.

The effect of cuproptosis-relevant genes on the immune infiltration and metabolism of gynecological oncology by multiply analysis and experiments validation

Gynecological cancers are a leading cause of mortality for women, including ovarian cancer (OC), cervical squamous cell carcinoma (CESC), and uterine corpus endometrial carcinoma (UCEC). Nevertheless, these gynecological cancer types have not elucidated the role of cuproptosis and the correlated tumor microenvironment (TME) infiltration features. CRGs had important potential molecular functions and prognostic significance in gynecological cancers, especially in UCEC. Hub CRG, FDX1, was correlated with the CD8+ T cell immune infiltration in UCEC and CESC. FDX1 OE could significantly repress the proliferation ability in UCEC cells by MTT, EdU, and clone formation. High levels of FDX1 could repress ATP and lactic acid but enhance ROS and glucose levels by metabolism assay. The xenograft tumor model indicated that FDX1 OE significantly inhibited the growth of UCEC and attenuated the PCNA, HK2, PKM2, and Ki-67 expression. These CRGs are significant roles that could be potential markers and treatment targets to optimize the TME immune cell infiltration features for gynecological cancer types. FDX1 is a hub CRGs in UCEC to promote immune infiltration and attenuate proliferation and metabolism.

The role and participation of immune cells in the endometrial tumor microenvironment

The tumor microenvironment is surrounded by blood vessels and consists of malignant, non-malignant, and immune cells, as well as signalling molecules, which primarily affect the therapeutic response and curative effects of drugs in clinical studies. Tumor-infiltrating immune cells participate in tumor progression, impact anticancer therapy, and eventually lead to the development of immune tolerance. Immunotherapy is evolving as a promising therapeutic intervention to stimulate and activate the immune system to suppress cancer cell growth. Endometrial cancer (EC) is an immunogenic disease, and in recent years, immunotherapy has shown benefit in the treatment of recurrent and advanced EC. This review discusses the key molecular pathways associated with the intra-tumoral immune response and the involvement of circulatory signalling molecules. Specific immunologic signatures in EC which offer targets for immunomodulating agents, are also discussed. We have summarized the available literature in support of using immunotherapy in EC. Lastly, we have also discussed ongoing clinical trials that may offer additional promising immunotherapy options in the future. The manuscript also explored innovative approaches for screening and identifying effective drugs, and to reduce the financial burdens for the development of personalized treatment strategies. Collectively, we aim to provide a comprehensive review of the role of immune cells and the tumor microenvironment in the development, progression, and treatment of EC.

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.

"Surface epithelial slackening" pattern in endometrioid carcinoma: A morphological feature for differentiating the POLE mutation-subtype from the no specific molecular profile subtype

Endometrial cancers are classified into mismatch repair (MMR) deficient- (MMRd), p53 mutation- (p53mut), DNA polymerase epsilon (POLE) mutation (POLEmut), and no specific molecular profile (NSMP) subtypes according to The Cancer Genome Atlas (TCGA). The distinction between POLEmut and NSMP subtypes is made on the basis of molecular analysis because the specific histological and immunohistochemical features of these two subtypes are still unknown. In this study, we analyzed histological features by scoring the presence of a mucinous pool, giant cells, clear cells, keratinization, neutrophilic abscess, and surface proliferating pattern in 82 cases of endometrial cancers in which an integrative diagnosis was confirmed by immunohistochemistry and genomic profiles showing POLE mutations, tumor mutation burden, and microsatellite instability. In contrast to the hierarchical branching of micropapillary proliferation observed in serous carcinoma, POLEmut-subtype endometrioid carcinomas often showed a surface epithelial slackening (SES) pattern in the tumor cells facing the uterine surface. The POLEmut subtype exhibited higher scores for clear cells and SES patterns than the other three subtypes. The scores for giant cells, clear cells, and the SES pattern were significantly higher in the POLEmut subtype than in the NSMP subtype, suggesting that these morphometric parameters are useful for differentiating POLEmut- and NSMP-subtype endometrioid carcinomas, although genomic profiling is still necessary for a definite molecular diagnosis.

The association between the tumor immune microenvironments and clinical outcome in low-grade, early-stage endometrial cancer patients

Endometrial tumors show substantial heterogeneity in their immune microenvironment. This heterogeneity could be used to improve the accuracy of current outcome prediction tools. We assessed the immune microenvironment of 235 patients diagnosed with low-grade, early-stage endometrial cancer. Multiplex quantitative immunofluorescence was carried out to measure CD8, CD68, FOXP3, PD-1, and PD-L1 markers, as well as cytokeratin (CK), on tissue microarrays. Clustering results revealed five robust immune response patterns, each associated with specific immune populations, cell phenotypes, and cell spatial clustering. Most samples (69%) belonged to the immune-desert subtype, characterized by low immune cell densities. Tumor-infiltrating lymphocyte (TIL)-rich samples (4%) displayed high CD8⁺ T-cell infiltration, as well as a high percentage of CD8/PD-1⁺ cells. Immune-exclusion samples (19%) displayed the lowest CD8⁺ infiltration combined with high PD-L1 expression levels in CK⁺ tumor cells. In addition, they demonstrated high tumor cell spatial clustering as well as increased spatial proximity of CD8⁺ /PD-1⁺ and CK/PD-L1⁺ cells. FOXP3 and macrophage-rich phenotypes (3% and 4% of total samples) displayed relatively high levels of FOXP3⁺ regulatory T-cells and CD68⁺ macrophages, respectively. These phenotypes correlated with clinical outcomes, with immune-exclusion tumors showing an association with tumor relapse. When compared with prediction models built using routine pathological variables, models optimized with immune variables showed increased outcome prediction capacity (AUC = 0.89 versus 0.78) and stratification potential. The improved prediction capacity was independent of mismatch repair protein status and adjuvant radiotherapy treatment. Further, immunofluorescence results could be partially recapitulated using single-marker immunohistochemistry (IHC) performed on whole tissue sections. TIL-rich tumors demonstrated increased CD8⁺ T-cells by IHC, while immune-exclusion tumors displayed a lack of CD8⁺ T-cells and frequent expression of PD-L1 in tumor cells. Our results demonstrate the capability of the immune microenvironment to improve standard prediction tools in low-grade, early-stage endometrial carcinomas. © 2022 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

Ferroptosis: Opportunities and Challenges in Treating Endometrial Cancer

Ferroptosis, a new way of cell death, is involved in many cancers. A growing number of studies have focused on the unique role of ferroptosis on endometrial cancer. In this study, we made a comprehensive review of the relevant articles published to get deep insights in the association of ferroptosis with endometrial cancer and to present a summary of the roles of different ferroptosis-associated genes. Accordingly, we made an evaluation of the relationships between the ferroptosis-associated genes and TNM stage, tumor grade, histological type, primary therapy outcome, invasion and recurrence of tumor, and accessing the different prognosis molecular typing based on ferroptosis-associated genes. In addition, we presented an introduction of the common drugs, which targeted ferroptosis in endometrial cancer. In so doing, we clarified the opportunities and challenges of ferroptosis activator application in treating endometrial cancer, with a view to provide a novel approach to the disease.

Using Weighted Gene Co-Expression Network Analysis to Identify Increased MND1 Expression as a Predictor of Poor Breast Cancer Survival

Objective

We used bioinformatics analysis to identify potential biomarker genes and their relationship with breast cancer (BC).

Materials and Methods

We used a weighted gene co-expression network analysis (WGCNA) to create a co-expression network based on the top 25% genes in the GSE24124, GSE33926, and GSE86166 datasets obtained from the Gene Expression Omnibus. We used the DAVID online platform to perform GO and KEGG pathway enrichment analyses and the Cytoscape CytoHubba plug-in to screen the potential genes. Then, we related the genes to prognostic values in BC using the Oncomine, GEPIA, and Kaplan–Meier Plotter databases. Findings were validated by immunohistochemical (IHC) staining in the Human Protein Atlas and the TCGA-BRCA cohort. LinkedOmics identified the interactive expressions of hub genes. We used UALCAN to evaluate the methylation levels of these hub genes. MethSurv and SurvivalMeth were used to assess the multilevel prognostic value. Finally, we assessed hub gene association with immune cell infiltration using TIMER.

Results

The mRNA levels of MKI67, UBE2C, GTSE1, CCNA2, and MND1 were significantly upregulated in BC, whereas ESR1, THSD4, TFF1, AGR2, and FOXA1 were significantly downregulated. The DNA methylation signature analysis showed a better prognosis in the low-risk group. Further subgroup analyses revealed that MND1 might serve as an independent risk factor for unfavorable BC prognosis. Additionally, MND1 expression levels positively correlate with the immune infiltration statuses of CD4+ T cells, CD8+ T cells, B cells, neutrophils, dendritic cells, and macrophages.

Conclusion

Our results indicate that the ten hub genes may be involved in BC’s carcinogenesis, development, or metastasis, and MND1 may be a potential biomarker and therapeutic target for BC.

Immunosuppressive tumor microenvironment in Uterine Serous Carcinoma via CCL7 signal with myeloid-derived suppressor cells

Serous carcinoma of the uterus (USC) is a pathological subtype of high-grade endometrial cancers, with no effective treatment for advanced cases. Since such refractory tumors frequently harbor anti-tumor immune tolerance, many immunotherapies have been investigated for various malignant tumors using immuno-competent animal models mimicking their local immunities. In this study, we established an orthotopic mouse model of high-grade endometrial cancer and evaluated the local tumor immunity to explore the efficacy of immunotherapies against USC. A multivariate analysis of 62 human USC cases revealed that the tumor infiltrating cell status, few CD8+ cells and abundant myeloid-derived suppressor cells (MDSCs), was an independent prognostic factor (p<0.005). A murine endometrial cancer cell (mECC) was obtained from C57BL/6 mice via endometrium-specific deletion of Pten and Tp53, and another high-grade cell (HPmECC) was established by further overexpressing Myc in mECCs. HPmECCs exhibited higher capacities of migration and anchorage-independent proliferation than mECCs (p<0.01, p<0.0001), and when both types of cells were inoculated into the uterus of C57BL/6 mice, the prognosis of mice bearing HPmECC-derived tumors was significantly poorer (p<0.001). Histopathological analysis of HPmECC orthotopic tumors showed serous carcinoma-like features with prominent tumor infiltration of MDSCs (p<0.05), and anti Gr-1 antibody treatment significantly prolonged the prognosis of HPmECC-derived tumor-bearing mice (p<0.05). High CCL7 expression was observed in human USC and HPmECC, and MDSCs migration was promoted in a CCL7 concentration-dependent manner. These results indicate that anti-tumor immunity is suppressed in USC due to increased number of tumor-infiltrating MDSCs via CCL signal.

Establishing a Prognostic Signature Based on Epithelial-Mesenchymal Transition-Related Genes for Endometrial Cancer Patients

Backgrounds

Epithelial-mesenchymal transition (EMT) is a sequential process where tumor cells develop from the epithelial state to the mesenchymal state. EMT contributes to various tumor functions including initiation, propagating potential, and resistance to therapy, thus affecting the survival time of patients. The aim of this research is to set up an EMT-related prognostic signature for endometrial cancer (EC).

Methods

EMT-related gene (ERG) expression and clinical data were acquired from The Cancer Genome Atlas (TCGA). The entire set was randomly divided into two sets, one for contributing the risk model (risk score) and the other for validating. Univariate and multivariate Cox proportional hazards regression analyses were applied to the training set to select the prognostic ERGs. The expression of 10 ERGs was confirmed by qRT-PCR in clinical samples. Then, we developed a nomogram predicting 1-/3-/5-year survival possibility combining the risk score and clinical factors. The entire set was stratified into the high- and low-risk groups, which was used to analyze the immune infiltrating, tumorigenesis pathways, and response to drugs.

Results

A total of 220 genes were screened out from 1,316 ERGs for their differential expression in tumor versus normal. Next, 10 genes were found to be associated with overall survival (OS) in EC, and the expression was validated by qRT-PCR using clinical samples, so we constructed a 10-ERG-based risk score to distinguish high-/low-risk patients and a nomogram to predict survival rate. The calibration plots proved the predictive value of our model. Gene Set Enrichment Analysis (GSEA) discovered that in the low-risk group, immune-related pathways were enriched; in the high-risk group, tumorigenesis pathways were enriched. The low-risk group showed more immune activities, higher tumor mutational burden (TMB), and higher CTAL4/PD1 expression, which was in line with a better response to immune checkpoint inhibitors. Nevertheless, response to chemotherapeutic drugs turned out better in the high-risk group. The high-risk group had higher N ⁶-methyladenosine (m⁶A) RNA expression, microsatellite instability level, and stemness indices.

Conclusion

We constructed the ERG-related signature model to predict the prognosis of EC patients. What is more, it might offer a reference for predicting individualized response to immune checkpoint inhibitors and chemotherapeutic drugs.

Development of an Oxidative Phosphorylation-Related and Immune Microenvironment Prognostic Signature in Uterine Corpus Endometrial Carcinoma

Background: As the fourth most common malignant tumors in women, uterine corpus endometrial carcinoma (UCEC) requires novel and reliable biomarkers for prognosis prediction to improve the overall survival. Oxidative phosphorylation (OXPHOS) is found to be strongly correlated with the progression of tumor. Here, we aimed to construct an OXPHOS-related and immune microenvironment prognostic signature to stratify UCEC patients for optimization of treatment strategies.

Method: Prognosis-associated OXPHOS-related differentially expressed genes were identified by multivariable Cox regression from TCGA–UCEC cohort. Based on the candidate genes, an OXPHOS-related prognostic signature was constructed by the train set data and verified by the entire set. When integrated with relevant clinical characteristics, a nomogram was also created for clinical application. Through comparison of tumor microenvironment between different risk groups, the underlying mechanism of the model and the inner correlation between immune microenvironment and energy metabolism were further investigated.

Results: An OXPHOS-related signature containing ATP5IF1, COX6B1, FOXP3, and NDUFB11 was constructed and had better predictive ability compared with other recently published signatures in UCEC. Patients with lower risk score showed higher immune cell infiltration, higher ESTIMATE score (p = 2.808E−18), lower tumor purity (p = 2.808E−18), higher immunophenoscores (IPSs) (p < 0.05), lower expression of mismatch repair (MMR) proteins (p < 0.05), higher microsatellite instability (MSI), lower expression of markers of N6-methyladenosine (m6A) mRNA methylation regulators, higher tumor mutation burden (TMB) (p = 1.278E−9), and more sensitivity to immune checkpoint blockade (ICB) (p < 0.001) and chemotherapy drugs, thus, possessing improved prognosis.

Conclusion: An OXPHOS-related and immune microenvironment prognostic signature classifying EC patients into different risk subsets was constructed in our study, which could be used to predict the prognosis of patients and help to select a specific subset of patients who might benefit from immunotherapy and chemotherapy, thus, improving the overall survival rate of UCEC. These findings may contribute to the discovery of novel and robust biomarkers or target therapy in UCEC and give new insights into the molecular mechanism of tumorigenesis and progression of UCEC.

Modulating microRNAs in cancer: Next-generation therapies

MicroRNAs (miRNAs) are a class of endogenously expressed non-coding regulators of the genome with an ability to mediate a variety of biological and pathological processes. There is growing evidence demonstrating frequent dysregulation of microRNAs in cancer cells, which is associated with tumor initiation, development, migration, invasion, resisting cell death, and drug resistance. Studies have shown that modulation of these small RNAs is a novel and promising therapeutic tool in the treatment of a variety of diseases, especially cancer, due to their broad influence on multiple cellular processes. However, suboptimal delivery of the appropriate miRNA to the cancer sites, quick degradation by nucleases in the blood circulation, and off target effects have limited their research and clinical applications. Therefore, there is a pressing need to improve the therapeutic efficacy of miRNA modulators, while at the same time reducing their toxicities. Several delivery vehicles for miRNA modulators have been shown to be effective in vitro and in vivo. In this review, we will discuss the role and importance of miRNAs in cancer and provide perspectives on currently available carriers for miRNA modulation. We will also summarize the challenges and prospects for the clinical translation of miRNA-based therapeutic strategies.

Proteomic Analysis of Low-Grade, Early-Stage Endometrial Carcinoma Reveals New Dysregulated Pathways Associated with Cell Death and Cell Signaling

Simple Summary

Low-grade, early-stage endometrial cancer (EC) is the most frequent malignant tumor of the uterine corpus. Our study aimed to assess dysregulated pathways in this specific subset of EC through proteomic analysis. We describe and validate the dysregulation of the SLIT/ROBO signaling pathway, as well as cellular death processes such as necroptosis and ferroptosis. We identify several immune-related pathways, with a dominance of innate immune response associated pathways. Our findings reveal the singular biology of low-grade, early-stage ECs and could guide future research in the field.

Abstract

Low-grade, early-stage endometrial carcinoma (EC) is the most frequent malignant tumor of the uterine corpus. However, the molecular alterations that underlie these tumors are far from being fully understood. The purpose of this study is to describe dysregulated molecular pathways from EC patients. Sixteen samples of tumor tissue and paired healthy controls were collected and both were subjected to mass spectrometry (MS)/MS proteomic analysis. Gene ontology and pathway analysis was performed to discover dysregulated pathways and/or proteins using different databases and bioinformatic tools. Dysregulated pathways were cross-validated in an independent external cohort. Cell signaling, immune response, and cell death-associated pathways were robustly identified. The SLIT/ROBO signaling pathway demonstrated dysregulation at the proteomic and transcriptomic level. Necroptosis and ferroptosis were cell death-associated processes aberrantly regulated, in addition to apoptosis. Immune response-associated pathways showed a dominance of innate immune responses. Tumor immune infiltrates measured by immunofluorescence demonstrated diverse lymphoid and myeloid populations. Our results suggest a role of SLIT/ROBO, necroptosis, and ferroptosis, as well as a prominent role of innate immune response in low-grade, early-stage EC. These results could guide future research in this group of tumors.

Reconstruction of Immune Microenvironment and Signaling Pathways in Endometrioid Endometrial Adenocarcinoma During Formation of Lymphovascular Space Involvement and Lymph Node Metastasis

Background

The amplification or mutation of oncogenes and escape from immune surveillance systems promote tumor metastasis. However, subtle changes in the immune microenvironment and signaling pathways are poorly understood during the formation of lymphovascular space involvement (LVSI) and lymph node (LN) metastasis of endometrioid endometrial adenocarcinoma (EEA).

Patients and methods

We detected tumor immunology-related signaling pathways and immunocyte subtypes according to the mRNA levels of 750 oncogenes and genes relating to the tumor microenvironment and immune response using the Nanostring PanCancer IO 360 Panel in 24 paraffin-embedded tissues of EEAs and benign gynecological diseases. Internal reference genes were used for data normalization.

Results

Angiogenesis and immune cell adhesion signaling pathways were activated during LVSI formation of EEA progression. However, during the development of LVSI to LN metastasis, immune system signaling pathways were significantly inhibited, including antigen presentation, cytotoxicity, lymphoid compartment, interferon signaling, and costimulatory signaling pathways. Immune-related genes (CD69, HLA-DOA, ATF3, GBP1, AP2, DTX3L, EGR1, GBP4, TAP1, EIF2AK2, MX1, ISG15, STAT1, and HLA-DRA) were significantly downregulated in EEA with LN metastasis compared to those in EEA with LVSI. Instead, hypoxia, metabolic stress, epigenetic regulation, matrix remodeling, and metastasis signaling pathways were continuously activated in LN metastasis. We also found that neutrophils, macrophages, and mast cells might be involved in LVSI formation and LN metastasis in EEA.

Conclusions

EEA with metastatic LNs showed significant immunosuppressive effects. Some oncogenes, matrix remodeling- and hypoxia-related genes, and neutrophil signatures showed higher expression, suggesting their potential as therapeutic targets and offering new immunotherapy strategies in EEA during LN metastasis.

Decreased PTGDS Expression Predicting Poor Survival of Endometrial Cancer by Integrating Weighted Gene Co-Expression Network Analysis and Immunohistochemical Validation

Purpose

To identify key pathogenic genes and reveal the potential molecular mechanisms of endometrial cancer (EC) using bioinformatics analysis and immunohistochemistry validation.

Materials and Methods

Through weighted gene co-expression network analysis (WGCNA), a co-expression network was constructed based on the top 25% variant genes in the GSE50830 dataset downloaded from gene expression omnibus (GEO). GO and KEGG pathway enrichment analyses were performed using the DAVID online tool. Candidate genes were selected using the cytoHubba plug-in of Cytoscape, mRNA expression levels and prognostic values in EC were analyzed by Oncomine, GEPIA, and Kaplan–Meier Plotter database to determine hub genes. One hub gene was validated by immunohistochemical (IHC) staining of 116 paraffin-embedded endometrial tissues and TCGA-UCEC cohort. Genes co-expressed with this hub gene were identified by LinkedOmics. Finally, its correlation with immune infiltration was evaluated by TIMER.

Results

Three co-expression modules and five candidate genes in each module were obtained by WGCNA; four hub genes were identified (LGR5, SST, ZNF558, and PTGDS). The mRNA levels of LGR5 and SST were significantly upregulated in EC, whereas those of ZNF558 and PTGDS were significantly downregulated; the expression of all four genes was associated with EC prognosis. Further validation demonstrated that PTGDS was significantly downregulated in the EC group compared with the atypical hyperplasia and normal endometrial groups, and its low expression was an independent risk factor for worse prognosis of EC. Biological function analysis indicated that PTGDS might be involved in the adaptive immune response, leukocyte migration, as well as in the regulation of cell adhesion molecules and chemokine signaling. Additionally, PTGDS expression was positively correlated with immune infiltration status of B cells, CD4⁺ T cells and macrophages.

Conclusion

LGR5, SST, ZNF558, and PTGDS may participate in the development, progression, and prognosis of EC, in which PTGDS may be a novel biomarker and therapeutic target for EC.

A Biomimetic Nanogenerator of Reactive Nitrogen Species Based on Battlefield Transfer Strategy for Enhanced Immunotherapy

Currently, cell membrane is always utilized for the construction of biomimetic nanoparticles. By contrast, mimicking the intracellular activity seems more meaningful. Inspired by the specific killing mechanism of deoxy-hemoglobin (Hb) dependent drug (RRx-001) in hypoxic red blood cells (RBC), this work aims to develop an inner and outer RBC-biomimetic antitumor nanoplatform that replicates both membrane surface properties and intracellularly certain therapeutic mechanisms of RRx-001 in hypoxic RBC. Herein, RRx-001 and Hb are introduced into RBC membrane camouflaged TiO₂ nanoparticles. Upon arrival at hypoxic tumor microenvironment (TME), the biomimetic nanoplatform (R@HTR) is activated and triggers a series of reactions to generate reactive nitrogen species (RNS). More importantly, the potent antitumor immunity and immunomodulatory function of RNS in TME are demonstrated. Such an idea would transfer the battlefield of RRx-001 from hypoxic RBC to hypoxic TME, enhancing its combat capability. As a proof of concept, this biomimetic nanoreactor of RNS exhibits efficient tumor regression and metastasis prevention. The battlefield transfer strategy would not only present meaningful insights for immunotherapy, but also realize substantial breakthroughs in biomimetic nanotechnology.

Endometrial Tumour Microenvironment

Endometrial cancer (EC) is the most common gynaecological tumour in developed countries, and its incidence is increasing in part due to the prevalence of obesity and its related hormone dysregulation. As described in this chapter, the tumour microenvironment plays a principal role in unopposed oestrogen stimulation promoting tumour cell proliferation. Factors and cytokines secreted by the different cell types defining the reactive tumour stroma also determine the invasive abilities of the tumour cells. Cancer-associated fibroblasts and tumour-associated macrophages actively participate through SDF-1, TGF-b or HGF to promote epithelial-to-mesenchymal transition or to generate an appropriate tumour niche. Likewise, endothelial cells facilitate lymph node and vascular infiltration through VEGF. Finally, the possibility to balance the immunosuppressive phenotypes in advanced endometrial cancer through the tumour microenvironment will probably represent a main therapeutic strategy in the near future.

Immunotherapy: Checkpoint Inhibitors in Lynch-Associated Gynecologic Cancers

OPINION STATEMENT

Research into novel therapies for gynecologic cancers is underfunded, and as a result, we are still playing catchup with other solid tumors in the realm of immune checkpoint inhibition. This is despite the fact that two of the most common gynecologic cancers in the USA have strong biologic rationales for response to these agents. Work is now underway to demonstrate safe and effective therapies for our patients. As we better understand the immune system, and more specifically the tumor microenvironment, we will be able to achieve complete responses. The immune system can learn, adapt, and provide ongoing surveillance; if only we could mimic its abilities.