ABSTRACT
Low-grade serous ovarian carcinoma (LGSC) is a rare and lethal subtype of ovarian cancer. LGSC is pathologically, biologically, and clinically distinct from the more common high-grade serous ovarian carcinoma (HGSC). LGSC arises from serous borderline ovarian tumours (SBTs). The mechanism of transformation for SBTs to LGSC remains poorly understood. To better understand the biology of LGSC, we performed whole proteome profiling of formalin-fixed, paraffin-embedded tissue blocks of LGSC (n = 11), HGSC (n = 19), and SBTs (n = 26). We identified that the whole proteome is able to distinguish between histotypes of the ovarian epithelial tumours. Proteins associated with the tumour microenvironment were differentially expressed between LGSC and SBTs. Fibroblast activation protein (FAP), a protein expressed in cancer-associated fibroblasts, is the most differentially abundant protein in LGSC compared with SBT. Multiplex immunohistochemistry (IHC) for immune markers (CD20, CD79a, CD3, CD8, and CD68) was performed to determine the presence of B cells, T cells, and macrophages. The LGSC FAP+ stroma was associated with greater abundance of Tregs and M2 macrophages, features not present in SBTs. Our proteomics cohort reveals that there are changes in the tumour microenvironment in LGSC compared with its putative precursor lesion, SBT. These changes suggest that the tumour microenvironment provides a supportive environment for LGSC tumourigenesis and progression. Thus, targeting the tumour microenvironment of LGSC may be a viable therapeutic strategy. © 2024 The Pathological Society of Great Britain and Ireland.
ABSTRACT
Histological transformation of follicular lymphoma (FL) to aggressive forms is associated with poor outcome. Phenotypic consequences of this evolution and its impact on the tumor microenvironment (TME) remain unknown. We perform single-cell whole genome sequencing (scWGS) and transcriptome sequencing (scWTS) of 11 paired pre/post-transformation patient samples and scWTS of additional samples from patients without transformation. Our analysis reveals evolutionary dynamics of transformation at single-cell resolution, highlighting a shifting TME landscape, with an emerging immune-cell exhaustion signature, co-evolving with the shifting malignant B phenotype in a regulatory ecosystem. Integration of scWGS and scWTS identifies malignant cell pathways upregulated during clonal tumor evolution. Using multi-color immunofluorescence, we transfer these findings to a TME-based transformation biomarker, subsequently validated in two independent pretreatment cohorts. Taken together, our results provide a comprehensive view of the combined genomic and phenotypic evolution of malignant cells during transformation and shifting crosstalk between malignant cells and the TME.
Subject(s)
Lymphoma, Follicular , Single-Cell Analysis , Tumor Microenvironment , Humans , Lymphoma, Follicular/genetics , Lymphoma, Follicular/pathology , Lymphoma, Follicular/immunology , Tumor Microenvironment/genetics , Tumor Microenvironment/immunology , Single-Cell Analysis/methods , Cell Transformation, Neoplastic/genetics , B-Lymphocytes/immunology , B-Lymphocytes/pathology , B-Lymphocytes/metabolism , Gene Expression Regulation, Neoplastic , Transcriptome , Biomarkers, Tumor/genetics , Whole Genome Sequencing , Gene Expression Profiling/methodsABSTRACT
In clinical oncology, many diagnostic tasks rely on the identification of cells in histopathology images. While supervised machine learning techniques necessitate the need for labels, providing manual cell annotations is time-consuming. In this paper, we propose a self-supervised framework (enVironment-aware cOntrastive cell represenTation learning: VOLTA) for cell representation learning in histopathology images using a technique that accounts for the cell's mutual relationship with its environment. We subject our model to extensive experiments on data collected from multiple institutions comprising over 800,000 cells and six cancer types. To showcase the potential of our proposed framework, we apply VOLTA to ovarian and endometrial cancers and demonstrate that our cell representations can be utilized to identify the known histotypes of ovarian cancer and provide insights that link histopathology and molecular subtypes of endometrial cancer. Unlike supervised models, we provide a framework that can empower discoveries without any annotation data, even in situations where sample sizes are limited.
Subject(s)
Endometrial Neoplasms , Ovarian Neoplasms , Humans , Female , Endometrial Neoplasms/pathology , Ovarian Neoplasms/pathology , Machine Learning , Supervised Machine Learning , Algorithms , Image Processing, Computer-Assisted/methodsABSTRACT
PURPOSE: About a third of patients with relapsed or refractory classic Hodgkin lymphoma (r/r CHL) succumb to their disease after high-dose chemotherapy followed by autologous stem-cell transplantation (HDC/ASCT). Here, we aimed to describe spatially resolved tumor microenvironment (TME) ecosystems to establish novel biomarkers associated with treatment failure in r/r CHL. PATIENTS AND METHODS: We performed imaging mass cytometry (IMC) on 71 paired primary diagnostic and relapse biopsies using a marker panel specific to CHL biology. For each cell type in the TME, we calculated a spatial score measuring the distance of nearest neighbor cells to the malignant Hodgkin Reed Sternberg cells within the close interaction range. Spatial scores were used as features in prognostic model development for post-ASCT outcomes. RESULTS: Highly multiplexed IMC data revealed shared TME patterns in paired diagnostic and early r/r CHL samples, whereas TME patterns were more divergent in pairs of diagnostic and late relapse samples. Integrated analysis of IMC and single-cell RNA sequencing data identified unique architecture defined by CXCR5+ Hodgkin and Reed Sternberg (HRS) cells and their strong spatial relationship with CXCL13+ macrophages in the TME. We developed a prognostic assay (RHL4S) using four spatially resolved parameters, CXCR5+ HRS cells, PD1+CD4+ T cells, CD68+ tumor-associated macrophages, and CXCR5+ B cells, which effectively separated patients into high-risk versus low-risk groups with significantly different post-ASCT outcomes. The RHL4S assay was validated in an independent r/r CHL cohort using a multicolor immunofluorescence assay. CONCLUSION: We identified the interaction of CXCR5+ HRS cells with ligand-expressing CXCL13+ macrophages as a prominent crosstalk axis in relapsed CHL. Harnessing this TME biology, we developed a novel prognostic model applicable to r/r CHL biopsies, RHL4S, opening new avenues for spatial biomarker development.
Subject(s)
Hodgkin Disease , Humans , Hodgkin Disease/drug therapy , Tumor Microenvironment , Ecosystem , Neoplasm Recurrence, Local , Treatment Outcome , RecurrenceABSTRACT
PURPOSE: Endometrioid ovarian carcinoma (ENOC) is the second most-common type of ovarian carcinoma, comprising 10%-20% of cases. Recently, the study of ENOC has benefitted from comparisons to endometrial carcinomas including defining ENOC with four prognostic molecular subtypes. Each subtype suggests differential mechanisms of progression, although tumor-initiating events remain elusive. There is evidence that the ovarian microenvironment may be critical to early lesion establishment and progression. However, while immune infiltrates have been well studied in high-grade serous ovarian carcinoma, studies in ENOC are limited. EXPERIMENTAL DESIGN: We report on 210 ENOC, with clinical follow-up and molecular subtype annotation. Using multiplex IHC and immunofluorescence, we examine the prevalence of T-cell lineage, B-cell lineage, macrophages, and populations with programmed cell death protein 1 or programmed death-ligand 1 across subtypes of ENOC. RESULTS: Immune cell infiltrates in tumor epithelium and stroma showed higher densities in ENOC subtypes with known high mutation burden (POLEmut and MMRd). While molecular subtypes were prognostically significant, immune infiltrates were not (overall survival P > 0.2). Analysis by molecular subtype revealed that immune cell density was prognostically significant in only the no specific molecular profile (NSMP) subtype, where immune infiltrates lacking B cells (TILB minus) had inferior outcome (disease-specific survival: HR, 4.0; 95% confidence interval, 1.1-14.7; P < 0.05). Similar to endometrial carcinomas, molecular subtype stratification was generally superior to immune response in predicting outcomes. CONCLUSIONS: Subtype stratification is critical for better understanding of ENOC, in particular the distribution and prognostic significance of immune cell infiltrates. The role of B cells in the immune response within NSMP tumors warrants further study.
Subject(s)
Carcinoma, Endometrioid , Endometrial Neoplasms , Ovarian Neoplasms , Female , Humans , Prognosis , Biomarkers, Tumor/genetics , Carcinoma, Endometrioid/pathology , Ovarian Neoplasms/pathology , Endometrial Neoplasms/genetics , Endometrial Neoplasms/pathology , Carcinoma, Ovarian Epithelial , Tumor MicroenvironmentABSTRACT
High-grade serous ovarian cancer (HGSC) is frequently characterized by homologous recombination (HR) DNA repair deficiency and, while most such tumors are sensitive to initial treatment, acquired resistance is common. We undertook a multiomics approach to interrogate molecular diversity in end-stage disease, using multiple autopsy samples collected from 15 women with HR-deficient HGSC. Patients had polyclonal disease, and several resistance mechanisms were identified within most patients, including reversion mutations and HR restoration by other means. We also observed frequent whole-genome duplication and global changes in immune composition with evidence of immune escape. This analysis highlights diverse evolutionary changes within HGSC that evade therapy and ultimately overwhelm individual patients.
Subject(s)
Cystadenocarcinoma, Serous , Ovarian Neoplasms , Humans , Female , Ovarian Neoplasms/genetics , Multiomics , Carcinoma, Ovarian Epithelial , Homologous Recombination/genetics , Cystadenocarcinoma, Serous/geneticsABSTRACT
OBJECTIVE: Mucinous ovarian carcinoma (MOC) is a rare histotype of ovarian cancer, with low response rates to standard chemotherapy, and very poor survival for patients diagnosed at advanced stage. There is a limited understanding of the MOC immune landscape, and consequently whether immune checkpoint inhibitors could be considered for a subset of patients. METHODS: We performed multicolor immunohistochemistry (IHC) and immunofluorescence (IF) on tissue microarrays in a cohort of 126 MOC patients. Cell densities were calculated in the epithelial and stromal components for tumor-associated macrophages (CD68+/PD-L1+, CD68+/PD-L1-), T cells (CD3+/CD8-, CD3+/CD8+), putative T-regulatory cells (Tregs, FOXP3+), B cells (CD20+/CD79A+), plasma cells (CD20-/CD79a+), and PD-L1+ and PD-1+ cells, and compared these values with clinical factors. Univariate and multivariable Cox Proportional Hazards assessed overall survival. Unsupervised k-means clustering identified patient subsets with common patterns of immune cell infiltration. RESULTS: Mean densities of PD1+ cells, PD-L1- macrophages, CD4+ and CD8+ T cells, and FOXP3+ Tregs were higher in the stroma compared to the epithelium. Tumors from advanced (Stage III/IV) MOC had greater epithelial infiltration of PD-L1- macrophages, and fewer PD-L1+ macrophages compared with Stage I/II cancers (p = 0.004 and p = 0.014 respectively). Patients with high epithelial density of FOXP3+ cells, CD8+/FOXP3+ cells, or PD-L1- macrophages, had poorer survival, and high epithelial CD79a + plasma cells conferred better survival, all upon univariate analysis only. Clustering showed that most MOC (86%) had an immune depleted (cold) phenotype, with only a small proportion (11/76,14%) considered immune inflamed (hot) based on T cell and PD-L1 infiltrates. CONCLUSION: In summary, MOCs are mostly immunogenically 'cold', suggesting they may have limited response to current immunotherapies.
Subject(s)
B7-H1 Antigen , Ovarian Neoplasms , Humans , Female , B7-H1 Antigen/genetics , Carcinoma, Ovarian Epithelial/pathology , Ovarian Neoplasms/drug therapy , CD8-Positive T-Lymphocytes , Forkhead Transcription Factors/therapeutic use , Lymphocytes, Tumor-Infiltrating , Tumor MicroenvironmentABSTRACT
Introduction: Targeted-immunotherapies such as antibody-drug conjugates (ADC), chimeric antigen receptor (CAR) T cells or bispecific T-cell engagers (eg, BiTE®) all aim to improve cancer treatment by directly targeting cancer cells while sparing healthy tissues. Success of these therapies requires tumor antigens that are abundantly expressed and, ideally, tumor specific. The CD34-related stem cell sialomucin, podocalyxin (PODXL), is a promising target as it is overexpressed on a variety of tumor types and its expression is consistently linked to poor prognosis. However, PODXL is also expressed in healthy tissues including kidney podocytes and endothelia. To circumvent this potential pitfall, we developed an antibody, named PODO447, that selectively targets a tumor-associated glycoform of PODXL. This tumor glycoepitope is expressed by 65% of high-grade serous ovarian carcinoma (HGSOC) tumors. Methods: In this study we characterize these PODO447-expressing tumors as a distinct subset of HGSOC using four different patient cohorts that include pre-chemotherapy, post-neoadjuvant chemotherapy (NACT) and relapsing tumors as well as tumors from various peritoneal locations. Results: We find that the PODO447 epitope expression is similar across tumor locations and negligibly impacted by chemotherapy. Invariably, tumors with high levels of the PODO447 epitope lack infiltrating CD8+ T cells and CD20+ B cells/plasma cells, an immune phenotype consistently associated with poor outcome. Discussion: We conclude that the PODO447 glycoepitope is an excellent biomarker of immune "cold" tumors and a candidate for the development of targeted-therapies for these hard-to-treat cancers.
ABSTRACT
Poorly differentiated chordoma (PDC) is a recently recognized subtype of chordoma characterized by expression of the embryonic transcription factor, brachyury, and loss of INI1. PDC primarily affects children and is associated with a poor prognosis and limited treatment options. Here we describe the molecular and immune tumour microenvironment profiles of two paediatric PDCs produced using whole-genome, transcriptome and whole-genome bisulfite sequencing (WGBS) and multiplex immunohistochemistry. Our analyses revealed the presence of tumour-associated immune cells, including CD8+ T cells, and expression of the immune checkpoint protein, PD-L1, in both patient samples. Molecular profiling provided the rationale for immune checkpoint inhibitor (ICI) therapy, which resulted in a clinical and radiographic response. A dominant T cell receptor (TCR) clone specific for a brachyury peptide-MHC complex was identified from bulk RNA sequencing, suggesting that targeting of the brachyury tumour antigen by tumour-associated T cells may underlie this clinical response to ICI. Correlative analysis with rhabdoid tumours, another INI1-deficient paediatric malignancy, suggests that a subset of tumours may share common immune phenotypes, indicating the potential for a therapeutically targetable subgroup of challenging paediatric cancers.
ABSTRACT
Lymphocyte-rich classic Hodgkin lymphoma (LR-CHL) is a rare subtype of Hodgkin lymphoma. Recent technical advances have allowed for the characterization of specific cross-talk mechanisms between malignant Hodgkin Reed-Sternberg (HRS) cells and different normal immune cells in the tumor microenvironment (TME) of CHL. However, the TME of LR-CHL has not yet been characterized at single-cell resolution. Here, using single-cell RNA sequencing (scRNA-seq), we examined the immune cell profile of 8 cell suspension samples of LR-CHL in comparison to 20 samples of the mixed cellularity (MC, 9 cases) and nodular sclerosis (NS, 11 cases) subtypes of CHL, as well as 5 reactive lymph node controls. We also performed multicolor immunofluorescence (MC-IF) on tissue microarrays from the same patients and an independent validation cohort of 31 pretreatment LR-CHL samples. ScRNA-seq analysis identified a unique CD4+ helper T cell subset in LR-CHL characterized by high expression of Chemokine C-X-C motif ligand 13 (CXCL13) and PD-1. PD-1+CXCL13+ T cells were significantly enriched in LR-CHL compared to other CHL subtypes, and spatial analyses revealed that in 46% of the LR-CHL cases these cells formed rosettes surrounding HRS cells. MC-IF analysis revealed CXCR5+ normal B cells in close proximity to CXCL13+ T cells at significantly higher levels in LR-CHL. Moreover, the abundance of PD-1+CXCL13+ T cells in the TME was significantly associated with shorter progression-free survival in LR-CHL (P = 0.032). Taken together, our findings strongly suggest the pathogenic importance of the CXCL13/CXCR5 axis and PD-1+CXCL13+ T cells as a treatment target in LR-CHL.
Subject(s)
B-Lymphocytes/metabolism , Chemokine CXCL13/metabolism , Hodgkin Disease/pathology , Receptors, CXCR5/metabolism , T-Lymphocytes, Helper-Inducer/metabolism , B7-H1 Antigen/metabolism , Fluorescent Antibody Technique , Humans , Lymph Nodes/cytology , Programmed Cell Death 1 Receptor/metabolism , RNA-Seq , Reed-Sternberg Cells/pathology , Single-Cell Analysis , Tumor Microenvironment/immunologyABSTRACT
BACKGROUND: Glioblastoma (GBM) is known to use both local and systemic immunosuppressive strategies. One such strategy is the expression of the immune checkpoint protein programmed cell death ligand-1 (PD-L1) by both tumor cells and tumor-associated immune cells. Recent phase III trials using IgG4 antibodies targeting PD-1, the ligand for PD-L1, failed to show any benefit. Avelumab is an IgG1 monoclonal antibody targeting PD-L1. In contrast to the previously tested immune checkpoint inhibitors, it can directly bind tumor cells and immune cells expressing PD-L1 and can induce antibody-dependent cellular cytotoxicity. METHODS: We conducted a single center, open label, phase II study where avelumab 10 mg/kg IV Q2W was added concurrently to the first monthly temozolomide cycle in patients with newly diagnosed GBM. Immunohistochemical analyses were performed on surgery samples. The primary objective was safety. Secondary objectives were efficacy outcomes according to the immunotherapy Response Assessment in Neuro Oncology criteria, progression free survival (PFS), and overall survival (OS). Exploratory objectives aimed at determining prognostic biomarkers. RESULTS: Thirty patients were started on therapy and two were lost to follow-up. Median follow-up time (reverse Kaplan-Meier) was 41.7 months (IQR: 28.3-43.4). Three (10.0%) patients had a related or possibly related treatment emergent adverse event that lead to transient or permanent discontinuation of avelumab. Eight (26.7%) patients had one or more immune-related adverse events, and 8 (26.7%) patients had an infusion-related reaction. The overall response rate was 23.3%, median PFS was 9.7 months, and the median OS was 15.3 months. No pretreatment biomarkers showed any predictive value. CONCLUSIONS: The addition of avelumab to standard therapy in patients with GBM was not associated with any new safety signal. There was no apparent improvement in OS. TRIAL REGISTRATION: NCT03047473 Registered February 9, 2017.
ABSTRACT
Triple negative breast cancer holds a dismal clinical outcome and as such, patients routinely undergo aggressive, highly toxic treatment regimens. Clinical trials for TNBC employing immune checkpoint blockade in combination with chemotherapy show modest prognostic benefit, but the percentage of patients that respond to treatment is low, and patients often succumb to relapsed disease. Here, we show that a combination immunotherapy platform utilizing low dose chemotherapy (FEC) combined with oncolytic virotherapy (oHSV-1) increases tumor-infiltrating lymphocytes, in otherwise immune-bare tumors, allowing 60% of mice to achieve durable tumor regression when treated with immune checkpoint blockade. Whole-tumor RNA sequencing of mice treated with FEC + oHSV-1 shows an upregulation of B cell receptor signaling pathways and depletion of B cells prior to the start of treatment in mice results in complete loss of therapeutic efficacy and expansion of myeloid-derived suppressor cells. Additionally, RNA sequencing data shows that FEC + oHSV-1 suppresses genes associated with myeloid-derived suppressor cells, a key population of cells that drive immune escape and mediate therapeutic resistance. These findings highlight the importance of tumor-infiltrating B cells as drivers of antitumor immunity and their potential role in the regulation of myeloid-derived suppressor cells.
Subject(s)
B-Lymphocytes/drug effects , Immune Checkpoint Inhibitors/therapeutic use , Immunotherapy/methods , Lymphocytes, Tumor-Infiltrating/drug effects , Myeloid-Derived Suppressor Cells/drug effects , Triple Negative Breast Neoplasms/therapy , Animals , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , B-Lymphocytes/immunology , B-Lymphocytes/metabolism , Cell Line, Tumor , Chlorocebus aethiops , Combined Modality Therapy , Female , Humans , Immune Checkpoint Inhibitors/immunology , Kaplan-Meier Estimate , Lymphocytes, Tumor-Infiltrating/immunology , Lymphocytes, Tumor-Infiltrating/metabolism , Mice, Inbred C57BL , Myeloid-Derived Suppressor Cells/immunology , Myeloid-Derived Suppressor Cells/metabolism , Oncolytic Virotherapy/methods , Triple Negative Breast Neoplasms/immunology , Triple Negative Breast Neoplasms/pathology , Vero CellsABSTRACT
PURPOSE: Tumor-infiltrating lymphocytes (TIL) are strongly associated with survival in most cancers; however, the tumor-reactive subset that drives this prognostic effect remains poorly defined. CD39, CD103, and PD-1 have been independently proposed as markers of tumor-reactive CD8+ TIL in various cancers. We evaluated the phenotype, clonality, and prognostic significance of TIL expressing various combinations of these markers in high-grade serous ovarian cancer (HGSC), a malignancy in need of more effective immunotherapeutic approaches. EXPERIMENTAL DESIGN: Expression of CD39, CD103, PD-1, and other immune markers was assessed by high-dimensional flow cytometry, single-cell sequencing, and multiplex immunofluorescence of primary and matched pre/post-chemotherapy HGSC specimens. RESULTS: Coexpression of CD39, CD103, and PD-1 ("triple-positive" phenotype) demarcated subsets of CD8+ TIL and CD4+ regulatory T cells (Treg) with a highly activated/exhausted phenotype. Triple-positive CD8+ TIL exhibited reduced T-cell receptor (TCR) diversity and expressed genes involved in both cytolytic and humoral immunity. Triple-positive Tregs exhibited higher TCR diversity and a tumor-resident phenotype. Triple-positive TIL showed superior prognostic impact relative to TIL expressing other combinations of these markers. TIGIT was uniquely upregulated on triple-positive CD8+ effector cells relative to their CD4+ Treg counterparts. CONCLUSIONS: Coexpression of CD39, CD103, and PD-1 demarcates highly activated CD8+ and CD4+ TIL with inferred roles in cytolytic, humoral, and regulatory immune functions. Triple-positive TIL demonstrate exceptional prognostic significance and express compelling targets for combination immunotherapy, including PD-1, CD39, and TIGIT.
Subject(s)
Cystadenocarcinoma, Serous/immunology , Cystadenocarcinoma, Serous/pathology , Lymphocytes, Tumor-Infiltrating , Ovarian Neoplasms/immunology , Ovarian Neoplasms/pathology , Antigens, CD/biosynthesis , Apyrase/biosynthesis , Cystadenocarcinoma, Serous/metabolism , Female , Humans , Integrin alpha Chains/biosynthesis , Lymphocytes, Tumor-Infiltrating/metabolism , Ovarian Neoplasms/metabolism , Prognosis , Programmed Cell Death 1 Receptor/biosynthesisABSTRACT
Pathological links between neurodegenerative disease and cancer are emerging. LRRK2 overactivity contributes to Parkinson's disease, whereas our previous analyses of public cancer patient data revealed that decreased LRRK2 expression is associated with lung adenocarcinoma (LUAD). The clinical and functional relevance of LRRK2 repression in LUAD is unknown. Here, we investigated associations between LRRK2 expression and clinicopathological variables in LUAD patient data and asked whether LRRK2 knockout promotes murine lung tumorigenesis. In patients, reduced LRRK2 was significantly associated with ongoing smoking and worse survival, as well as signatures of less differentiated LUAD, altered surfactant metabolism and immunosuppression. We identified shared transcriptional signals between LRRK2-low LUAD and postnatal alveolarization in mice, suggesting aberrant activation of a developmental program of alveolar growth and differentiation in these tumors. In a carcinogen-induced murine lung cancer model, multiplex IHC confirmed that LRRK2 was expressed in alveolar type II (AT2) cells, a main LUAD cell-of-origin, while its loss perturbed AT2 cell morphology. LRRK2 knockout in this model significantly increased tumor initiation and size, demonstrating that loss of LRRK2, a key Parkinson's gene, promotes lung tumorigenesis.
Subject(s)
Adenocarcinoma/chemically induced , Adenocarcinoma/genetics , Carcinogens/toxicity , Genetic Predisposition to Disease , Leucine-Rich Repeat Serine-Threonine Protein Kinase-2/genetics , Lung Neoplasms/chemically induced , Lung Neoplasms/genetics , Parkinson Disease/genetics , Adenocarcinoma/pathology , Cell Differentiation , Cocarcinogenesis , Genomic Instability , Humans , Lung Neoplasms/pathology , SmokingABSTRACT
OBJECTIVE: Chimeric antigen receptor (CAR)-T cell strategies ideally target a surface antigen that is exclusively and uniformly expressed by tumors; however, no such antigen is known for high-grade serous ovarian carcinoma (HGSC). A potential solution involves combinatorial antigen targeting with AND or OR logic-gating. Therefore, we investigated co-expression of CA125, Mesothelin (MSLN) and Folate Receptor alpha (FOLRA) on individual tumor cells in HGSC. METHODS: RNA expression of CA125, MSLN, and FOLR1 was assessed using TCGA (HGSC) and GTEx (healthy tissues) databases. Antigen expression profiles and CD3+, CD8+ and CD20+ tumor-infiltrating lymphocyte (TIL) patterns were assessed in primary and recurrent HGSC by multiplex immunofluorescence and immunohistochemistry. RESULTS: At the transcriptional level, each antigen was overexpressed in >90% of cases; however, MSLN and FOLR1 showed substantial expression in healthy tissues. At the protein level, CA125 was expressed by the highest proportion of cases and tumor cells per case, followed by MSLN and FOLRA. The most promising pairwise combination was CA125 and/or MSLN (OR gate), with 51.9% of cases containing ≥90% of tumor cells expressing one or both antigens. In contrast, only 5.8% of cases contained ≥90% of tumor cells co-expressing CA125 and MSLN (AND gate). Antigen expression patterns showed modest correlations with TIL. Recurrent tumors retained expression of all three antigens and showed increased TIL densities. CONCLUSIONS: An OR-gated CAR-T cell strategy against CA125 and MSLN would target the majority of tumor cells in most cases. Antigen expression and T-cell infiltration patterns are favorable for this strategy in primary and recurrent disease.
Subject(s)
Antigens, Neoplasm/metabolism , Carcinoma, Ovarian Epithelial/immunology , Immunotherapy, Adoptive/methods , Neoplasm Recurrence, Local/immunology , Ovarian Neoplasms/immunology , Receptors, Chimeric Antigen/metabolism , Antigens, Neoplasm/immunology , CA-125 Antigen/immunology , CA-125 Antigen/metabolism , Carcinoma, Ovarian Epithelial/pathology , Carcinoma, Ovarian Epithelial/therapy , Female , Folate Receptor 1/immunology , Folate Receptor 1/metabolism , GPI-Linked Proteins/immunology , GPI-Linked Proteins/metabolism , Gene Expression Profiling , Humans , Lymphocytes, Tumor-Infiltrating/immunology , Membrane Proteins/immunology , Membrane Proteins/metabolism , Mesothelin , Neoplasm Recurrence, Local/pathology , Neoplasm Recurrence, Local/therapy , Ovarian Neoplasms/pathology , Ovarian Neoplasms/therapy , Ovary/immunology , Ovary/pathology , Receptors, Chimeric Antigen/immunologyABSTRACT
Anti-PD1/PDL1 therapy has proven efficacious against many cancers but only reached modest objective response rates against recurrent ovarian cancer. A deeper understanding of the tumor microenvironment (TME) may reveal other immunosuppressive mechanisms that warrant investigation as immunotherapeutic targets for this challenging disease. Matched primary and recurrent tumors from patients with high-grade serous ovarian carcinoma (HGSC) were analyzed by multicolor immunohistochemistry/immunofluorescence for the presence of T cells, B cells, macrophages, and for the expression of immunosuppressive and HLA molecules. Cancer- and immune-related gene expression was assessed by NanoString analysis. Recurrent tumors showed increased infiltration by immune cells, displayed higher expression of PDL1, IDO, and HLA molecules, and contained more stromal tissue. NanoString analysis demonstrated increased expression of gene signatures related to chemokines and T cell functions in recurrent tumors. The ovarian tumors showed high gene expression of LAG3 and HAVCR2 (TIM3) and enhanced levels of TIGIT and CTLA4 in recurrent tumors compared to primary tumors. The majority of HGSC developed into a more inflamed phenotype during progression from primary to recurrent disease, including indications of adaptive immune resistance. This suggests that recurrent tumors may be particularly sensitive to inhibition of adaptive immune resistance mechanisms.
ABSTRACT
Immune therapy is a promising field within oncology but has been unsuccessful in ovarian cancer (OC). Still, there is rationale and evidence supporting immune therapy in OC. We investigated the potential for adoptive cell therapy (ACT) from in vitro expanded tumor-infiltrating lymphocytes (TILs) in combination with checkpoint inhibitors (ICI) and conducted immunological testing of ex vivo expanded TILs (REP-TILs). Six patients with late-stage metastatic high-grade serous OC were treated with immune therapy consisting of ipilimumab followed by surgery to obtain TILs and infusion of REP-TILs, low-dose IL-2 and nivolumab. One patient achieved a partial response and 5 others experienced disease stabilization for up to 12 months. Analysis of the REP-TILs with flow- and mass-cytometry show primarily activated and differentiated effector memory T cells. REP-TILs showed in vitro reactivity and expression of inhibitory receptors, such as LAG-3 and PD-1. Furthermore, our data indicate that addition of ipilimumab therapy improves the T cell fold expansion during production, increase the level of CD8 T cell tumor reactivity, and favorably affect the T cell phenotype. We show that the combination of ICI and ACT is feasible and safe. With one partial response and one long-lasting SD, we demonstrated the potential of ACT in OC.
ABSTRACT
Tumor-targeted chimeric antigen receptor (CAR)-engineered T lymphocytes (CAR-T cells) have demonstrated striking clinical success, but their use has been associated with a constellation of toxicities. A better understanding of the pathogenesis of these toxicities is required to improve the safety profile of CAR-T cells. Herein, we describe a xenograft model of off-tumor CAR-T cell-associated toxicity. Human CAR-T cells targeted against HER2 using a small-protein binding domain induced acute, dose-dependent toxicities in mice. The inclusion of a CD28 or 4-1BB co-stimulatory domain in the CAR was required to produce toxicity; however, co-stimulation through CD28 was most toxic on a per-cell basis. CAR-T cell activation in the lungs and heart was associated with a systemic cytokine storm. The severity of observed toxicities was dependent upon the peripheral blood mononuclear cell (PBMC) donor used as a T cell source and paralleled the CD4+-to-CD8+ T cell ratio in the adoptive transfer product. CD4+ CAR-T cells were determined to be the primary contributors to CAR-T cell-associated toxicity. However, donor-specific differences persisted after infusion of a purified CD4+ CAR-T cell product, indicating a role for additional variables. This work highlights the contributions of CAR-T cell-intrinsic variables to the pathogenesis of off-tumor toxicity.
ABSTRACT
OBJECTIVE: We recently showed that tumors with an immunologically 'cold' phenotype are enriched for expression of stemness-associated genes and PVR/CD155, the ligand of the immunosuppressive molecule TIGIT. To explore the therapeutic implications of this finding, we investigated the relationship between PVR/CD155 expression, tumor-infiltrating lymphocytes (TIL), and prognosis in high-grade serous ovarian cancer (HGSC) and other cancers. METHODS: Expression of CD155, TIGIT, PD-1, PD-L1, and other immune markers in HGSC was assessed by high-dimensional flow cytometry, multi-color histological imaging, and/or gene expression profiling. The prognostic significance of PVR/CD155 and CD274/PD-L1 expression was assessed bioinformatically in HGSC and 32 other cancers in The Cancer Genome Atlas. RESULTS: T cells from HGSC frequently co-expressed TIGIT and PD-1, and the ratio of TIGIT to PD-1 expression increased markedly after in vitro expansion with a clinically relevant protocol. CD155 was commonly expressed on malignant epithelium in HGSC and showed a negative or non-significant association with TIL. In contrast, PD-L1 was predominantly expressed by tumor-associated macrophages and positively associated with TIL. These contrasts between CD155 and PD-L1 were seen across HGSC patients, across metastatic sites within individual patients, and even within individual tumor deposits. PVR/CD155 and CD274/PD-L1 exhibited divergent prognostic associations across diverse cancer types in TCGA, including HGSC. CONCLUSIONS: CD155 and PD-L1 exhibit contrasting expression patterns, TIL associations and prognostic significance, suggesting they represent non-redundant immunosuppressive mechanisms. The CD155/TIGIT pathway represents a compelling immunotherapeutic target for HGSC and for immunologically cold tumors in general.