Tumor-infiltrating immune cell profiles and their change after neoadjuvant chemotherapy predict response and prognosis of breast cancer

Quantitative Multiplex Immunofluorescence Evaluation of the Tumor Microenvironment in Pretreatment Tumors of Patients with Metastatic Breast Cancer and Serous Ovarian Carcinoma Treated with Liposomal Eribulin

Eribulin inhibits microtubule polymerization and suppresses epithelial-mesenchymal transition. Conventional pathology approaches have not identified a precise predictive biomarker for Eribulin. We performed qmIF on pre-treatment tissue from 11 patients (6 TNBC, 5 HGSOC) treated with Eribulin-LF. T-lymphocytes were the dominant immune-subset in TME, with higher levels detected in stroma vs tumor (9% vs 2%). Greater density of CD3+ (p = 0.01) and CD3 + CD8+ (p = 0.03) cells and closer proximity between CD3 + CD8+ and tumor cells was observed in the patients with disease control (PR + SD) vs. progressive disease. QmIF identified an association between TIL infiltration and Eribulin-LF sensitivity, which should be evaluated further in prospective studies.

Immunotherapy in breast cancer: A clinician's perspective

Globally over 2 million women are diagnosed with breast cancer each year despite major advances in detection and treatment of the disease. Breast cancer is comprised of several distinct subtypes and understanding the heterogeneity of the disease has become crucial for treatment planning. Therapeutic strategies span from a hormone therapy-based focus for women with estrogen receptor positive breast cancer to targeting human epidermal growth factor (HER2) by small molecules, antibody-drug-conjugates (ADC) and monoclonal antibodies in those with HER2 overexpression. Other novel treatment strategies for select subgroups of patients include the cyclin-dependent kinase 4/6 (CDK4/6) inhibitors for women with estrogen receptor positive tumors, the poly ADP ribose polymerase (PARP) inhibitors for those with BRCA mutations, and phosphoinositide 3-kinase (PI3K) inhibitors for women with tumors harboring phophatidylinositol-4,5-bisphosphate 3 kinase catalytic subunit alpha (PIK3CA) mutations. In contrast, the treatment for women with triple negative breast cancer has until recently been solely limited to chemotherapy. The profound impact of immunotherapy on cancer treatment in general has created much hope for its potential in breast cancer. This review will focus on the current advances and the research of immunotherapy in breast cancer, particularly on immune checkpoint inhibitors, adoptive cell transfer and cancer vaccines.

Immune Crosstalk Between Lymph Nodes and Breast Carcinomas, With a Focus on B Cells

Lymph nodes (LNs) are highly organized secondary lymphoid organs, and reflective of immune responses to infection, injuries, or the presence of cancer. Extensive molecular and morphological analyses of immune and stromal features in tumors and LNs of breast cancer patients have revealed novel patterns indicative of disease progression. Within LNs, there are dynamic structures called germinal centers (GCs), that act as the immunological hubs for B cell development and generation of affinity matured memory B and antibody-producing plasma cells. Acting as a bridge between systemic and local immunity, associations are observed between the frequency of GCs within cancer-free LNs, the levels of stromal tumor infiltrating lymphocytes, and cancer progression. Scattered throughout the tumor microenvironment (TME) or aggregated in clusters forming tertiary lymphoid structures (TLS), the occurrence of tumor infiltrating B cells (TIL-Bs) has been linked mostly to superior disease trajectories in solid cancers. Recent TIL-Bs profiling studies have revealed a plethora of different TIL-B populations, their functional roles, and whether they are derived from GC reactions in the LN, and/or locally from GC-like structures within the TME remains to be investigated. However, parallels between the immunogenic nature of LNs as a pre-metastatic niche, TIL-B populations within the TME, and the presence of TLS will help to decipher local and widespread TIL-Bs responses and their influence on cancer progression to the lymphatics. Therapies that enhance TIL-Bs responses in the LN GC and/or in GC-like structures in the TME are thus emerging management strategies for breast and other cancer patients.

T cells, B cells, and PD-L1 expression in esophageal and gastric adenocarcinoma before and after neoadjuvant chemotherapy: relationship with histopathological response and survival

Perioperative chemotherapy enhances the survival rates for patients with esophageal and gastric (EG) adenocarcinoma, but not all patients benefit from this additional treatment. Chemotherapeutic agents have been demonstrated to alter the immune cell (IC) composition in the tumor microenvironment. Hence, there is a rationale to investigate the influence of neoadjuvant chemotherapy (NAC) on different IC subsets, to better understand and compare their utility as complementary prognostic or predictive biomarkers in a clinically relevant context. The density of T cells (CD8⁺ and FoxP3⁺), B cells (CD20⁺) and the expression of PD-L1 on ICs and tumor cells (TC) was assessed by immunohistochemistry on paired biopsies from primary tumors (PT) pre-NAC, and resected PT and lymph node metastases post-NAC. The cohort encompasses 148 patients with resectable EG adenocarcinoma, all of whom received NAC. The density of CD8⁺ cells was decreased and the density of FoxP3⁺ cells and CD20⁺ cells was increased in PT post-NAC. PD-L1 expression was not altered following NAC. In pre-NAC specimens, high FoxP3⁺ density and high PD-L1 expression on ICs were favorable prognostic factors, whereas high CD8⁺ density was an unfavorable prognostic factor. In post-NAC specimens, however, high FoxP3⁺ density was an unfavorable prognostic factor, and high PD-L1 expression on TC was associated with a shorter survival. There were no significant associations between IC density or PD-L1 expression in PT pre-NAC and histopathological regression. These findings propose that NAC might alter the density and prognostic impact of some IC subsets in EG adenocarcinoma.

Next-Generation Digital Histopathology of the Tumor Microenvironment

Progress in cancer research is substantially dependent on innovative technologies that permit a concerted analysis of the tumor microenvironment and the cellular phenotypes resulting from somatic mutations and post-translational modifications. In view of a large number of genes, multiplied by differential splicing as well as post-translational protein modifications, the ability to identify and quantify the actual phenotypes of individual cell populations in situ, i.e., in their tissue environment, has become a prerequisite for understanding tumorigenesis and cancer progression. The need for quantitative analyses has led to a renaissance of optical instruments and imaging techniques. With the emergence of precision medicine, automated analysis of a constantly increasing number of cellular markers and their measurement in spatial context have become increasingly necessary to understand the molecular mechanisms that lead to different pathways of disease progression in individual patients. In this review, we summarize the joint effort that academia and industry have undertaken to establish methods and protocols for molecular profiling and immunophenotyping of cancer tissues for next-generation digital histopathology-which is characterized by the use of whole-slide imaging (brightfield, widefield fluorescence, confocal, multispectral, and/or multiplexing technologies) combined with state-of-the-art image cytometry and advanced methods for machine and deep learning.

Tertiary lymphoid structures and B lymphocytes in cancer prognosis and response to immunotherapies

Tertiary lymphoid structures (TLS) are ectopic cellular aggregates that resemble secondary lymphoid organs in their composition and structural organization. In contrast to secondary lymphoid organs, TLS are not imprinted during embryogenesis but are formed in non-lymphoid tissues in response to local inflammation. TLS structures exhibiting a variable degree of maturation are found in solid tumors. They are composed of various immune cell types including dendritic cells and antigen-specific B and T lymphocytes, that together, actively drive the immune response against tumor development and progression. This review highlights the successive steps leading to tumor TLS formation and its association with clinical outcomes. We discuss the role played by tumor-infiltrating B lymphocytes and plasma cells, their prognostic value in solid tumors and immunotherapeutic responses and their potential for future targeting.

Profiles of immune infiltration and its relevance to survival outcome in meningiomas

Tumor-infiltrating immune cells play a decisive part in prognosis and survival. Until now, previous researches have not made clear about the diversity of cell types involved in the immune response. The objective of this work was to confirm the composition of tumor-infiltrating immune cells and their correlation with prognosis in meningiomas based on a metagene approach (known as CIBERSORT) and online databases. A total of 22 tumor-infiltrating immune cells were detected to determine the relationship between the immune infiltration pattern and survival. The proportion of M2 macrophages was more abundant in 68 samples, reaching more than 36%. Univariate Cox regression analysis displayed that the proportion of dendritic cells was obviously related to prognosis. Hierarchical clustering analysis identified two clusters by the method of within sum of squares errors, which exhibited different infiltrating immune cell composition and survival. To summarize, our results indicated that proportions of tumor-infiltrating immune cells as well as cluster patterns were associated with the prognosis, which offered clinical significance for research of meningiomas.

[Prediction of Response to Neoadjuvant Chemotherapy for Breast Cancer Based on Histomorphology Analysis of Needle Biopsy Images]

OBJECTIVE

The deep learning method was used to automatically segment the tumor area and the cell nucleus based on needle biopsy images of breast cancer patients prior to receiving neoadjuvant chemotherapy (NAC), and then, the features of the cell clusters in the tumor area were identified to predict the level of pathological remission of breast cancer after NAC.

METHODS

68 breast cancer patients who were to receive NAC at Jiangsu Province Hospital were recruited and the hematoxylin-eosin (HE) stained preoperative biopsy sections of these patients were collected. Unet++ was used to establish a segmentation model and the tumor area and nucleus of the needle biopsy images were automatically segmented accordingly. Then, according to the nuclei in the automatically segmented tumor area, the features of the cells in the tumor were constructed. After that, effective features were selected through the feature selection method and the classifier model was constructed and trained with five-fold cross validation to predict the degree of post-NAC pathological remission.

RESULTS

Predictions were made based on the needle biopsy images of the 68 patients. The model that combined the 10-dimensional features selected with the minimal redundancy-maximum-relevancy approach (mRMR) and training with the random forest (RF) classifier had the highest prediction accuracy, reaching 82.35%, and an area under curve ( AUC) value of 0.908 2.

CONCLUSION

This model automatically segments tumor areas and cell nucleus on the biopsy images. The features of the cell clusters which are analyzed and identified in the tumor area can be used to predict the pathological response of the patient to NAC. The method is reliable and replicable. In addition, we found that the textural features of cells in the tumor area was a useful predictor of patient response to NAC, which further confirmed that cell cluster in the tumor area is of great significance to the prediction of treatment outcome.

The Role of Immune Cells in Breast Tissue and Immunotherapy for the Treatment of Breast Cancer

Immune cells are present in normal breast tissue and in breast carcinoma. The nature and distribution of the immune cell subtypes in these tissues are reviewed to promote a better understanding of their important role in breast cancer prevention and treatment. We conducted a review of the literature to define the type, location, distribution, and role of immune cells in normal breast tissue and in in situ and invasive breast cancer. Immune cells in normal breast tissue are located predominantly within the epithelial component in breast ductal lobules. Immune cell subtypes representing innate immunity (NK, CD68+, and CD11c+ cells) and adaptive immunity (most commonly CD8+, but CD4+ and CD20+ as well) are present; CD8+ cells are the most common subtype and are primarily effector memory cells. Immune cells may recognize neoantigens and endogenous and exogenous ligands and may serve in chronic inflammation and immunosurveillance. Progression to breast cancer is characterized by increased immune cell infiltrates in tumor parenchyma and stroma, including CD4+ and CD8+ granzyme B+ cytotoxic T cells, B cells, macrophages and dendritic cells. Tumor-infiltrating lymphocytes in breast cancer may serve as prognostic indicators for response to chemotherapy and for survival. Experimental strategies of adoptive transfer of breast tumor-infiltrating lymphocyte may allow regression of metastatic breast cancer and encourage development of innovative T-cell strategies for the immunotherapy of breast cancer. In conclusion, immune cells in breast tissues play an important role throughout breast carcinogenesis. An understanding of these roles has important implications for the prevention and the treatment of breast cancer.

Immune Infiltrates in Breast Cancer: Recent Updates and Clinical Implications

In recent decades, the increasing interest in the field of immunotherapy has fostered an intense investigation of the breast cancer (BC) immune microenvironment. In this context, tumor-infiltrating lymphocytes (TILs) have emerged as a clinically relevant and highly reproducible biomarker capable of affecting BC prognosis and response to treatment. Indeed, the evaluation of TILs on primary tumors proved to be strongly prognostic in triple-negative (TN) BC patients treated with either adjuvant or neoadjuvant chemotherapy, as well as in early TNBC patients not receiving any systemic treatment, thus gaining level-1b evidence in this setting. In addition, a strong relationship between TILs and pathologic complete response after neoadjuvant chemotherapy has been reported in all BC subtypes and the prognostic role of higher TILs in early HER2-positive breast cancer patients has also been demonstrated. The interest in BC immune infiltrates has been further fueled by the introduction of the first immune checkpoint inhibitors in the treatment armamentarium of advanced TNBC in patients with PD-L1-positive status by FDA-approved assays. However, despite these advances, a biomarker capable of reliably and exhaustively predicting immunotherapy benefit in BC is still lacking, highlighting the imperative need to further deepen this issue. Finally, more comprehensive evaluation of immune infiltrates integrating both the quantity and quality of tumor-infiltrating immune cells and incorporation of TILs in composite scores encompassing other clinically or biologically relevant biomarkers, as well as the adoption of software-based and/or machine learning platforms for a more comprehensive characterization of BC immune infiltrates, are emerging as promising strategies potentially capable of optimizing patient selection and stratification in the research field. In the present review, we summarize available evidence and recent updates on immune infiltrates in BC, focusing on current clinical applications, potential clinical implications and major unresolved issues.

Targeting E-selectin to Tackle Cancer Using Uproleselan

E-selectin is a vascular adhesion molecule expressed mainly on endothelium, and its primary role is to facilitate leukocyte cell trafficking by recognizing ligand surface proteins. E-selectin gained a new role since it was demonstrated to be involved in cancer cell trafficking, stem-like properties and therapy resistance. Therefore, being expressed in the tumor microenvironment, E-selectin can potentially be used to eradicate cancer. Uproleselan (also known as GMI-1271), a specific E-selectin antagonist, has been tested on leukemia, myeloma, pancreatic, colon and breast cancer cells, most of which involve the bone marrow as a primary or as a metastatic tumor site. This novel therapy disrupts the tumor microenvironment by affecting the two main steps of metastasis-extravasation and adhesion-thus blocking E-selectin reduces tumor dissemination. Additionally, uproleselan mobilized cancer cells from the protective vascular niche into the circulation, making them more susceptible to chemotherapy. Several preclinical and clinical studies summarized herein demonstrate that uproleselan has favorable safety and pharmacokinetics and is a tumor microenvironment-disrupting agent that improves the efficacy of chemotherapy, reduces side effects such as neutropenia, intestinal mucositis and infections, and extends overall survival. This review highlights the critical contribution of E-selectin and its specific antagonist, uproleselan, in the regulation of cancer growth, dissemination, and drug resistance in the context of the bone marrow microenvironment.

The integration of proportion and cell counts of stromal, not intratumoral, PD-1+ tumor-infiltrating lymphocytes has prognostic significance in esophageal squamous cell carcinoma

The present study aimed to investigate the prognostic effect of intratumoral and stromal exhausted tumor-infiltrating lymphocytes (TILs) on operable esophageal cancer patients. We performed a retrospective cohort study by consecutively recruiting 142 patients with esophageal cancer. The proportion and cell counts of intratumoral and stromal PD-1+ TILs in tumor microenvironment were independently evaluated by two pathologists. Neither proportion nor cell counts of intratumoral PD-1+ TILs was associated with prognosis (p > 0.05). However, patients with the proportion of stromal PD1+ TILs >20% had the median overall survival (OS) at 19 months, significantly longer than those with the proportion = 20%. The adjusted hazard ratio (HR) was 1.49 (95%CI 0.82, 2.69). Patients with cell counts of stromal PD1+ TILs = 18/ high-power field (HPF) had the median disease-free survival (DFS) at 10 months. However, patients with cell counts>18/HPF had the median DFS at 48 months (p = 0.037), and the adjusted HR was 0.59 (95%CI 0.35, 1.01). Compared with patients with proportion = 20% and cell counts >18/HPF of stromal PD1+ TILs, patients with proportion = 20% and cell counts = 18/HPF, proportion >20% and cell counts >18/HPF, and proportion >20% and cell counts = 18/HPF, had the adjusted HRs increased to 3.73, 3.36 and 3.99 for DFS (p for trend being 0.030) and the adjusted HRs increased to 2.95, 3.64 and 3.82 (p for trend being 0.015) for OS, respectively. The integration of proportion and cell counts of PD-1+ stromal TILs has a significant association with the relapse and overall survival of esophageal cancer patients. Further prospective studies are warranted.

Recent Discoveries of Macromolecule- and Cell-Based Biomarkers and Therapeutic Implications in Breast Cancer

Breast cancer is the most commonly diagnosed cancer type and the leading cause of cancer-related mortality in women worldwide. Breast cancer is fairly heterogeneous and reveals six molecular subtypes: luminal A, luminal B, HER2+, basal-like subtype (ER−, PR−, and HER2−), normal breast-like, and claudin-low. Breast cancer screening and early diagnosis play critical roles in improving therapeutic outcomes and prognosis. Mammography is currently the main commercially available detection method for breast cancer; however, it has numerous limitations. Therefore, reliable noninvasive diagnostic and prognostic biomarkers are required. Biomarkers used in cancer range from macromolecules, such as DNA, RNA, and proteins, to whole cells. Biomarkers for cancer risk, diagnosis, proliferation, metastasis, drug resistance, and prognosis have been identified in breast cancer. In addition, there is currently a greater demand for personalized or precise treatments; moreover, the identification of novel biomarkers to further the development of new drugs is urgently needed. In this review, we summarize and focus on the recent discoveries of promising macromolecules and cell-based biomarkers for the diagnosis and prognosis of breast cancer and provide implications for therapeutic strategies.

Therapeutic and Systemic Adverse Events of Immune Checkpoint Inhibitors Targeting the PD-1/PD-L1 axis for Clinical Management of NSCLC

Non-small-cell lung cancer takes up the majority of lung carcinoma-caused deaths. It is reported that targeting PD-1/PD-L1, a well-known immune evasion checkpoint, can eradicate tumor. Checkpoint inhibitors, such as monoclonal antibodies, are actively employed in cancer treatment. Thus, this review aimed to assess the therapeutic and toxic effects of PD-1/PD-L1 inhibitors in treatment of NSCLC. So far, 6 monoclonal antibodies blocking PD-1/PD-L1 interaction are identified and used in clinical trials and randomized controlled trials for NSCLC therapy. These antibody-based therapies for NSCLC were collected by using search engine PubMed, and articles about the assessment of adverse events were collected by using Google search. Route of administration and dosage are critical parameters for efficient immunotherapy. Although antibodies can improve overall survival and are expected to be target-specific, they can cause systemic adverse effects in the host. Targeting certain biomarkers can limit the toxicity of adverse effects of the antibody-mediated therapy. Clinical experts with knowledge of adverse effects (AEs) of checkpoint inhibitors can help manage and reduce mortalities associated with antibody-based therapy of NSCLC.

Tumor-Infiltrating Lymphocytes in Low-Risk Patients With Breast Cancer Treated With Single-Dose Preoperative Partial Breast Irradiation

PURPOSE

Preoperative partial breast irradiation (PBI) has the potential to induce tumor regression. We evaluated the differences in the numbers of preirradiation tumor infiltrating lymphocytes (TILs) between responders and nonresponders after preoperative PBI in low-risk patients with breast cancer. Furthermore, we evaluated the change in number of TILs before and after irradiation.

METHODS AND MATERIALS

In the prospective ABLATIVE study, low-risk patients with breast cancer underwent treatment with single-dose preoperative PBI (20 Gy) to the tumor and breast-conserving surgery after 6 or 8 months. In the preirradiation diagnostic biopsy and postirradiation resection specimen, numbers of TILs in 3 square regions of 450 × 450 μm were counted manually. TILs were visualized with CD3, CD4, and CD8 immunohistochemistry. Differences in numbers of preirradiation TILs between responders and nonresponders were tested using Mann-Whitney U test. Responders were defined as pathologic complete or near-complete response, and nonresponders were defined "as all other response." Changes in numbers of TILs after preoperative PBI was evaluated with the Wilcoxon signed rank test.

RESULTS

Preirradiation tissue was available from 28 patients, postirradiation tissue from 29 patients, resulting in 22 pairs of preirradiation and postirradiation tissue. In these 35 patients, 15 had pathologic complete response (43%), 11 had a near-complete response (31%), 7 had a partial response (20%), and 2 had stable disease (6%). The median numbers of CD3⁺ TILs, CD4⁺ TILs, and CD8⁺ TILs in the preirradiation tumor tissue were 49 (interquartile range [IQR], 36-80), 45 (IQR, 28-57), and 19 (IQR, 8-35), respectively. The number of preirradiation TILs did not differ significantly between responders and nonresponders. The median numbers of CD3⁺ TILs, CD4⁺ TILs, and CD8⁺ TILs in postirradiation tumor tissue were 17 (IQR, 13-31), 26 (IQR, 16-35), and 7 (IQR, 5-11), respectively.

CONCLUSIONS

After preoperative PBI in this limited cohort, the number of TILs in tumor tissue decreased. No differences in numbers of preirradiation TILs between responders and nonresponders were observed.

Prognostic value of tumor-infiltrating lymphocyte subtypes in residual tumors of patients with triple-negative breast cancer after neoadjuvant chemotherapy

Background:

After neoadjuvant chemotherapy (NAC), non-pathological complete response of breast cancer patients can benefit from tailored adjuvant chemotherapy. However, it is difficult to select patients with poorer prognosis for additional adjuvant chemotherapy to maximize the benefits. Our study aimed to explore whether the subtypes of tumor-infiltrating lymphocytes (TILs) in residual tumors (RT) is related to the prognosis of triple-negative breast cancer (TNBC) after NAC.

Methods:

Data from patients with primary TNBC consecutively diagnosed at the Breast Disease Center of Peking University First Hospital from 2008 to 2014 were retrieved, and the cases with RT in the breast after NAC were enrolled. TILs subtypes in RT were observed by double-staining immunohistochemistry, and counted with the median TILs value per square millimeter as the cut-off to define high versus low TILs density in each subtype. The relationships between the TIL density of each subgroup and the clinicopathological characteristics of the RT after NAC patients were analyzed by Fisher exact test. Disease-free survival (DFS) and overall survival (OS) were analyzed by the Kaplan-Meier method and log-rank statistics.

Results:

A total of 37 eligible patients were included in this study, and the median follow-up period was 50 months (range 17–106 months). There was no significant correlation between the infiltrate density of CD4⁺, CD8⁺, CD20⁺, and CD68⁺ lymphocytes and clinic-pathological characteristics. Significantly better prognosis was observed in patients with high CD4⁺-TILs (DFS: P = 0.005, OS: P = 0.021) and high CD8⁺-TILs (DFS: P = 0.018) and low CD20⁺-TILs (OS: P = 0.042). Further analysis showed that patients with CD4⁺/CD20⁺ ratio greater than 1 (DFS: P = 0.001, OS: P = 0.002) or CD8⁺/CD20⁺ ratio greater than 1 (DFS: P = 0.009, OS: P = 0.022) had a better prognosis.

Conclusions:

Subtypes of TILs in RT is a potential predictive biomarker of survival in TNBC patients after NAC.

Chemotherapy-induced changes in bronchoalveolar lavage fluid CD4 + and CD8 + cells of the opposite lung to the cancer

Published articles support the effect of chemotherapy in the immune environment of tumors, including lung carcinomas. The role of CD4 + T-cells is crucial for expansion and accumulation of other antigen-specific immune cells, and the participation of CD8 + cells in tumor killing activity has been confirmed by many studies. However, little is known about the effect of chemotherapy on the healthy lung parenchyma from lung cancer patients, and whether there are differences between the different chemotherapy compounds used to treat this patient population. The aim of our study was to explore the effect of chemotherapy on CD4 + and CD8 + cells in the bronchoalveolar lavage fluid (BALF) of the healthy lung in patients treated with standard chemotherapy regimens. Fifteen patients underwent BAL, in the healthy lung before and after six chemotherapy courses. Platinum-based regimens included vinolerbine (VN) in 6 patients, gemcitabine (GEM) in 4 patients and etoposide (EP) in 5 patients. All patients but one were males and smokers (93%). The median age of patients was 56 years (42-75). No significant difference was noted in the patients' age between the three treated groups. Furthermore, between the three groups, no significant changes in the means of CD4 + and CD8 + cells were noted. However, when we compared the mean CD4 + cells before and after chemotherapy within each group, changes were noted when comparing VN before versus after (p = 0.05), GEM before versus after (p = 0.03), and EP before versus after (p = 0.036). In our pilot study, changes were noted in BALF CD4 + cells for the three most applied regimens at the normal lung parenchyma.

Peripheral cytotoxic T lymphocyte predicts first-line progression free survival in HER2-positive advanced breast cancer

Background

The role of peripheral blood lymphocyte (pBL) in breast cancer has long been studied. However, the predictive role of pBL in advanced breast cancer (ABC) is poorly understood.

Methods

A total of 303 patients with ABC were consecutively recruited at our center between January 2015 and September 2019. At baseline, pBL subtypes were detected in all patients with 229 blood samples available for circulating tumor DNA (ctDNA) detection. pBL was analyzed through flow cytometry. ctDNA-based gene mutations were detected using next generation sequencing. The cutoff value of pCTL was estimated by X-tile software. Progression free survival (PFS) was estimated by Kaplan-Meier curve and Cox hazard proportion regression model, with difference detection by log-rank test.

Results

Median follow-up time of the study was 21.0 months. The median age of diagnosis was 52.0 years. Among the pBL subtypes, only pCTL level was found predictive for PFS in the HER2+ patients whom received anti-HER2 therapy (13.1 vs. 5.6 months, P = 0.001). However, the predictive role of pCTL was not found in HR-positive (P = 0.716) and TNBC (P = 0.202). pCTL high associated with suppressive immune indictors including lower CD4/CD8 ratio (P = 0.004) and high level of Treg cell (P = 0.004). High occurrence of FGFR1 amplification which has been reported as immune suppressor was also found in HER2+ patients with pCTL high (22.2% vs. 4.3%, P = 0.048).

Conclusions

Higher pCTLs level associated with shorter PFS and FGFR1 mutation in HER2+ ABC patients.

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High pCTL level predicts shorter first-line PFS in HER2+ patients receiving anti-HER2 based regimens.

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The predictive role of pCTL level found in HER2+ patients was not applicable in HR+ and TNBC patients.

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High level of pCTL was associated with immunosuppressive status and FGFR1 mutations in HER2+ breast cancer patients.

Immune factors associated with the pathological and therapeutic effects of preoperative chemotherapy in patients with breast cancer

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The immune factors that determine the pathological and therapeutic effects of preoperative chemotherapy in patients with breast cancer are associated with local and systemic immune responses in the presence of tumor-infiltrating lymphocytes, in collaboration with downregulation of immunosuppressive factors mediated by vascular endothelial growth factor (VEGF) and cytotoxic T lymphocyte antigen 4 (CTLA-4) in regulatory T cells (Tregs) in the tumor microenvironment.

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Multivariate analysis showed that grade 2 and better therapeutic effects tended to be associated with higher natural killer cell levels after preoperative chemotherapy (odds ratio = 1.02; 95% confidence interval, 0.99–1.05; p = 0.07).

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Therapy targeting VEGF and CTLA-4 in Tregs to overcome tumor-derived immunosuppression may enhance the pathological and therapeutic responses to preoperative chemotherapy in patients with breast cancer.

Immune activation plays an important role in achieving the pathological and therapeutic effects of preoperative chemotherapy in patients with breast cancer. We evaluated how the immune response contributes to various therapeutic effects. This study was conducted on 43 patients with stages II–IV breast cancer who received preoperative chemotherapy followed by surgery. Peripheral natural killer (pNK) cell activity and the neutrophil-lymphocyte ratio, lymphocyte-monocyte ratio, and platelet-lymphocyte ratio (PLR) were assessed before and after chemotherapy. Tumor-infiltrating lymphocytes (TILs) and levels of 14 tumor microenvironmental factors, analyzed by next-generation sequencing, were assessed in formalin-fixed, paraffin-embedded sections of preoperative biopsy samples and surgical specimens. Univariate analysis showed that grade 2 (G2) and better therapeutic effects were significantly associated with human epidermal growth factor receptor 2 (HER-2)-positive cancer, lower PLRs, and higher NK cell and interleukin-6 levels after chemotherapy. The disappearance of axillary lymph-node metastasis was significantly associated with HER-2-positive cancer; increased pNK cell activity and lower PLRs and vascular endothelial growth factor (VEGF) levels after chemotherapy; and increased cytotoxic T lymphocyte antigen 4 (CTLA-4) levels in regulatory T cells (Tregs) and ≥5% TILs before chemotherapy. Multivariate analysis showed that G2 and better therapeutic effects tended to be associated with higher NK cell levels after chemotherapy (odds ratio = 1.02; 95% confidence interval, 0.99–1.05; P = 0.07). The activation of local and systemic immune responses by downregulation of immunosuppressive factors, such as VEGF and CTLA-4 in Tregs, had variable pathological and therapeutic effects after preoperative chemotherapy in patients with breast cancer.

Regulatory B cells and T cell Regulation in Cancer

Recent researches shed light on B cell role on various autoimmune diseases, including autoantibody-mediated diseases as well as T cell-mediated autoimmune diseases such as multiple sclerosis and rheumatoid arthritis. B cells play a critical role in the immune response beyond the production of antibodies through mechanisms such as antigen presentation and cytokine production. Furthermore, B cells have recently been recognized to play a role in promoting tumor immunity against cancer. However, not all B cells positively regulate immune responses. Regulatory B cells negatively regulate immune responses by the production of anti-inflammatory cytokines such as interleukin (IL)-10, IL-35, and transforming growth factor-beta. Thus, a balance between effector and regulatory B cells regulates the immune response through the release of cytokines. In this review, we highlight the main emerging roles of B cells in tumor immunity with a focus on the T cell response. These findings can guide a protocol for selectively depleting regulatory B cells as a potential therapeutic strategy for patients with cancer.

Prognostic Impact of Stromal Immune Infiltration before and after Neoadjuvant Chemotherapy (NAC) in Triple Negative Inflammatory Breast Cancers (TNIBC) Treated with Dose-Dense Dose-Intense NAC

Inflammatory breast cancers are very aggressive, and among them, triple negative breast cancer (TNBC) has the worst prognosis. While many studies have investigated the association between tumor-infiltrating lymphocytes (TIL) before neoadjuvant chemotherapy (NAC) and outcome in TNBC, the impact of post-NAC TIL and TIL variation in triple negative inflammatory breast cancer (TNIBC) outcome is unknown. Between January 2010 to December 2018, all patients with TNIBC seen at the breast disease unit (Saint-Louis Hospital) were treated with dose-dense dose-intense NAC. The main objective of the study was to determine factors associated with event-free survival (EFS), particularly pathological complete response (pCR), pre- and post-NAC TIL, delta TIL and post-NAC lymphovascular invasion (LVI). After univariate analysis, post-NAC LVI (HR 2.06; CI 1.13-3.74; p = 0.02), high post-NAC TIL (HR 1.81; CI 1.07-3.06; p = 0.03) and positive delta TIL (HR 2.20; CI 1.36-3.52; p = 0.001) were significantly associated with impaired EFS. After multivariate analysis, only a positive TIL variation remained negatively associated with EFS (HR 1.88; CI 1.05-3.35; p = 0.01). TNIBC patients treated with intensive NAC who present TIL enrichment after NAC have a high risk of relapse, which could be used as a prognostic marker in TNIBC and could help to choose adjuvant post-NAC treatment.

Quantitative multiplex immunofluorescence analysis identifies infiltrating PD1+ CD8+ and CD8+ T cells as predictive of response to neoadjuvant chemotherapy in breast cancer

Background

This study aimed to explore the potentially predictive role and dynamic changes of immune checkpoints on T cell subsets in patients with breast cancer receiving neoadjuvant chemotherapies.

Methods

Fluorescent multiplex immunohistochemistry (mIHC) was used to stain CD4, CD8, PD1, TIM3, and cytokeratins simultaneously in paired breast cancer samples before and after neoadjuvant therapies (NAT) in a prospective cohort (n = 50). Singleplex IHC was conducted to stain for CD3 in 100 cases with inclusion of extra retrospective 50 cases. Cell levels were correlated with clinicopathological parameters and pathological complete response (pCR).

Results

In pretreatment tumors, the percentages of infiltrating CD8⁺, PD1⁺, PD1⁺CD8⁺, and the ratio of PD1⁺CD8⁺/CD8⁺ cells, were higher in pCR than non‐pCR patients in either the stromal or intratumoral area, but PD1⁺CD4⁺, TIM3⁺CD4⁺, TIM3⁺CD8⁺ cells and CD4⁺/CD8⁺ ratio was not. Multivariate analyses showed that the percentage of intratumoral CD8⁺ cells (OR, 1.712; 95% CI: 1.052–2.786; P = 0.030) and stromal PD1⁺CD8⁺/CD8⁺ ratio (OR, 1.109; 95% CI: 1.009–1.218; P = 0.032) were significantly associated with pCR. Dynamically, reduction in the percentages of PD1⁺, CD8⁺ and PD1⁺CD8⁺ cells after therapy strongly correlated with pCR. Notably, incremental percentages of PD1⁺CD8⁺ cells, rather than TIM3⁺CD8⁺, were shown in tumors from non‐pCR patients after NAT. CD3 staining confirmed the percentage of T cells were associated with pCR.

Conclusions

PD1⁺CD8⁺ rather than TIM3⁺CD8⁺ cells are main predictive components within tumor‐infiltrating T cells in NAT breast cancer patients. Dynamically incremental levels of PD1⁺CD8⁺ cells occurred in non‐pCR cases after NAT, suggesting the combination of chemotherapy with PD1 inhibition might benefit these patients.

Key points

Significant findings of the study

PD1⁺CD8⁺, rather than TIM3⁺CD8⁺, T cells are the main component to predict the response of neoadjuvant therapies in breast cancer.

What this study adds

Incremental levels of PD1⁺CD8⁺ T cells in non‐pCR post‐NAT tumors suggest PD1 inhibition might benefit in the neoadjuvant setting.

Perspectives on Triple-Negative Breast Cancer: Current Treatment Strategies, Unmet Needs, and Potential Targets for Future Therapies

Triple-negative breast cancer (TNBC), characterized by the absence or low expression of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor (HER2), is the most aggressive subtype of breast cancer. TNBC accounts for about 15% of breast cancer cases in the U.S., and is known for high relapse rates and poor overall survival (OS). Chemo-resistant TNBC is a genetically diverse, highly heterogeneous, and rapidly evolving disease that challenges our ability to individualize treatment for incomplete responders and relapsed patients. Currently, the frontline standard chemotherapy, composed of anthracyclines, alkylating agents, and taxanes, is commonly used to treat high-risk and locally advanced TNBC. Several FDA-approved drugs that target programmed cell death protein-1 (Keytruda) and programmed death ligand-1 (Tecentriq), poly ADP-ribose polymerase (PARP), and/or antibody drug conjugates (Trodelvy) have shown promise in improving clinical outcomes for a subset of TNBC. These inhibitors that target key genetic mutations and specific molecular signaling pathways that drive malignant tumor growth have been used as single agents and/or in combination with standard chemotherapy regimens. Here, we review the current TNBC treatment options, unmet clinical needs, and actionable drug targets, including epidermal growth factor (EGFR), vascular endothelial growth factor (VEGF), androgen receptor (AR), estrogen receptor beta (ERβ), phosphoinositide-3 kinase (PI3K), mammalian target of rapamycin (mTOR), and protein kinase B (PKB or AKT) activation in TNBC. Supported by strong evidence in developmental, evolutionary, and cancer biology, we propose that the K-RAS/SIAH pathway activation is a major tumor driver, and SIAH is a new drug target, a therapy-responsive prognostic biomarker, and a major tumor vulnerability in TNBC. Since persistent K-RAS/SIAH/EGFR pathway activation endows TNBC tumor cells with chemo-resistance, aggressive dissemination, and early relapse, we hope to design an anti-SIAH-centered anti-K-RAS/EGFR targeted therapy as a novel therapeutic strategy to control and eradicate incurable TNBC in the future.

Immunostimulation with chemotherapy in the era of immune checkpoint inhibitors

Conventional chemotherapeutics have been developed into clinically useful agents based on their ability to preferentially kill malignant cells, generally owing to their elevated proliferation rate. Nonetheless, the clinical activity of various chemotherapies is now known to involve the stimulation of anticancer immunity either by initiating the release of immunostimulatory molecules from dying cancer cells or by mediating off-target effects on immune cell populations. Understanding the precise immunological mechanisms that underlie the efficacy of chemotherapy has the potential not only to enable the identification of superior biomarkers of response but also to accelerate the development of synergistic combination regimens that enhance the clinical effectiveness of immune checkpoint inhibitors (ICIs) relative to their effectiveness as monotherapies. Indeed, accumulating evidence supports the clinical value of combining appropriately dosed chemotherapies with ICIs. In this Review, we discuss preclinical and clinical data on the immunostimulatory effects of conventional chemotherapeutics in the context of ICI-based immunotherapy.

Gene signature-based prediction of triple-negative breast cancer patient response to Neoadjuvant chemotherapy

Neoadjuvant chemotherapy is the current standard of care for large, advanced, and/or inoperable tumors, including triple‐negative breast cancer. Although the clinical benefits of neoadjuvant chemotherapy have been illustrated through numerous clinical trials, more than half of the patients do not experience therapeutic benefit and needlessly suffer from side effects. Currently, no clinically applicable biomarkers are available for predicting neoadjuvant chemotherapy response in triple‐negative breast cancer; the discovery of such a predictive biomarker or marker profile is an unmet need. In this study, we introduce a generic computational framework to calculate a response‐probability score (RPS), based on patient transcriptomic profiles, to predict their response to neoadjuvant chemotherapy. We first validated this framework in ER‐positive breast cancer patients and showed that it predicted neoadjuvant chemotherapy response with equal performance to several clinically used gene signatures, including Oncotype DX and MammaPrint. Then, we applied this framework to triple‐negative breast cancer data and, for each patient, we calculated a response probability score (TNBC‐RPS). Our results indicate that the TNBC‐RPS achieved the highest accuracy for predicting neoadjuvant chemotherapy response compared to previously proposed 143 gene signatures. When combined with additional clinical factors, the TNBC‐RPS achieved a high prediction accuracy for triple‐negative breast cancer patients, which was comparable to the prediction accuracy of Oncotype DX and MammaPrint in ER‐positive patients. In conclusion, the TNBC‐RPS accurately predicts neoadjuvant chemotherapy response in triple‐negative breast cancer patients and has the potential to be clinically used to aid physicians in stratifying patients for more effective neoadjuvant chemotherapy.

Priming the tumor immune microenvironment with chemo(radio)therapy: A systematic review across tumor types

BACKGROUND

Chemotherapy (CT), radiotherapy (RT), and chemoradiotherapy (CRT) are able to alter the composition of the tumor immune microenvironment (TIME). Understanding the effect of these modalities on the TIME could aid in the development of improved treatment strategies. Our aim was to systematically review studies investigating the influence of CT, RT or CRT on different TIME markers.

METHODS

The EMBASE (Ovid) and PubMed databases were searched until January 2019 for prospective or retrospective studies investigating the dynamics of the local TIME in cancer patients (pts) treated with CT, RT or CRT, with or without targeted agents. Studies could either compare baseline and follow-up specimens - before and after treatment - or a treated versus an untreated cohort. Studies were included if they used immunohistochemistry and/or flow cytometry to assess the TIME.

RESULTS

In total we included 110 studies (n = 8850 pts), of which n = 89 (n = 6295 pts) compared pre-treatment to post-treatment specimens and n = 25 (n = 2555 pts) a treated versus an untreated cohort (4 studies conducted both comparisons). For several tumor types (among others; breast, cervical, esophageal, ovarian, rectal, lung mesothelioma and pancreatic cancer) remodeling of the TIME was observed, leading to a potentially more immunologically active microenvironment, including one or more of the following: an increase in CD3 or CD8 lymphocytes, a decrease in FOXP3 Tregs and increased PD-L1 expression. Both CT and CRT were able to immunologically alter the TIME.

CONCLUSION

The TIME of several tumor types is significantly altered after conventional therapy creating opportunities for concurrent or sequential immunotherapy.

Changes and prognostic values of tumor-infiltrating lymphocyte subsets after primary systemic therapy in breast cancer

Tumor-infiltrating lymphocyte (TIL) levels have prognostic and predictive values in treatment-naïve breast cancers. However, there have been controversies regarding TIL subset changes and their clinical implications in post-treatment breast cancers. This study aimed to explore change and prognostic significance of TIL subset infiltration after primary systemic therapy (PST) in breast cancer. One-hundred-fifty-five patients who had residual disease after anthracycline- or anthracycline plus taxane-based PST were included. The quantities of intratumoral and stromal TIL subsets (CD8+, CD4+, and FOXP3+ TILs) in pre- and post-PST breast cancer samples, as well as changes between them, were analyzed along with their correlations with clinicopathologic features and outcome of patients. As a whole, intratumoral CD8+ and CD4+ TILs increased after PST while stromal TILs decreased. Both intratumoral and stromal FOXP3+ TILs decreased after PST. The chemo-sensitive group [residual cancer burden (RCB) class I and II] showed the same pattern of change in intratumoral CD8+ TILs as the whole group, whereas the chemo-resistant group (RCB class III) showed no significant change in intratumoral CD8+ TIL infiltration after PST. Survival analyses for each TIL subset as well as their ratios revealed that high levels of intratumoral, stromal, and total CD8+ TIL infiltration after PST were independent predictors of longer patient survival. In subgroup analyses, CD8+ TIL infiltration after PST revealed prognostic significance in the chemo-resistant group but not in the chemo-sensitive group. In conclusion, infiltration of CD8+, CD4+, and FOXP3+ TIL changed after PST in the intratumoral and stromal compartments. Especially, increase of intratumoral CD8+ TILs was associated with chemo-responsiveness. Moreover, CD8+ TIL status in residual tumors after PST may be used as a potential prognostic marker in breast cancer patients who receive PST and provide additional prognostic information to chemo-resistant group.

The prognostic significance of immune microenvironment in breast ductal carcinoma in situ

BACKGROUND

The role of different subtypes of tumour infiltrating lymphocytes (TILs) in breast ductal carcinoma in situ (DCIS) is still poorly defined. This study aimed to assess the prognostic significance of B and T lymphocytes and immune checkpoint proteins expression in DCIS.

METHODS

A well characterised DCIS cohort (n = 700) with long-term follow-up comprising pure DCIS (n = 508) and DCIS mixed with invasive carcinoma (IBC; n = 192) were stained immunohistochemically for CD20, CD3, CD4, CD8, FOXP3, PD1 and PDL1. Copy number variation and TP53 mutation status were assessed in a subset of cases (n = 58).

RESULTS

CD3+ lymphocytes were the predominant cell subtype in the pure DCIS cohort, while FOXP3 showed the lowest levels. PDL1 expression was mainly seen in the stromal TILs. Higher abundance of TILs subtypes was associated with higher tumour grade, hormone receptor negativity and HER2 positivity. Mutant TP53 variants were associated with higher levels of stromal CD3+, CD4+ and FOXP3+ cells. DCIS coexisting with invasive carcinoma harboured denser stromal infiltrates of all immune cells and checkpoint proteins apart from CD4+ cells. Stromal PD1 was the most differentially expressed protein between DCIS and invasive carcinoma (Z = 5.8, p < 0.0001). Dense TILs, stromal FOXP3 and PDL1 were poor prognostic factors for DCIS recurrence, while dense TILs were independently associated with poor outcome for all recurrences (HR = 7.0; p = 0.024), and invasive recurrence (HR = 2.1; p = 0.029).

CONCLUSIONS

Immunosuppressive proteins are potential markers for high risk DCIS and disease progression. Different stromal and intratumoural lymphocyte composition between pure DCIS, DCIS associated with IBC and invasive carcinoma play a potential role in their prognostic significance and related to the underlying genomic instability. Assessment of overall TILs provides a promising tool for evaluation of the DCIS immune microenvironment.

Interferon-α2b enhances survival and modulates transcriptional profiles and the immune response in melanoma patients treated with dendritic cell vaccines

Malignant melanoma (MM) is the most lethal cutaneous cancer and is associated with 80 % of skin cancer deaths. Recent progress into elucidating the role of the immune system in melanoma development and progression has led to promising treatments for patients with MM, including dendritic cell (DC) vaccination. Interferon-α2b is a commonly used adjuvant for MM that prolongs overall survival (OS) and progression-free survival (PFS). In the present study, we examined the impact of a DC-based vaccine with subsequent delivery of high-dose systemic interferon-α2b (HDI) on gene expression profiles and the immune response in MM patients. The results indicated that patients who were randomized to receive an HDI boost following DC vaccination had significantly higher OS and PFS rates compared with patients that received DC vaccination alone. Further analysis revealed that intradermal DC immunization did not significantly alter transcriptional profiles, whereas subsequent HDI injections enhanced B cell, T cell and natural killer cell-related gene expression. Analysis of the abundance of tumor-infiltrating immune cells revealed that HDI altered the immune cell profiles. Moreover, we determined that follicular helper T (Tfh) cells and eosinophils were associated with prolonged PFS in MM patients treated with the DC vaccine.

Prognostic Factors and Tumor Infiltrating Lymphocytes in Triple Negative Breast Cancer

Objective

Triple-negative-breast-cancer (TNBC) is a very heterogenous disease some of which are very aggressive and have poor prognosis. No targeted therapy is available. Immune response and tumor-infiltrating lymphocytes (TIL) can be related to longer disease-free survival (DFS) and overall survival (OS) in TNBC. Family history of cancer can be related poor prognosis, irrespective of genetic mutation.

Materials and Methods

Pathology reports and files of 167 patients operated for TNBC were assessed retrospectively. The effects of lymphocyte infiltration, family history of cancer and other tumor characteristics on prognosis were evaluated. Data of 137 patients was included in statistical analysis.

Results

Univariate-analysis revealed that stage, size of tumor, histological subtype, number of infiltrated axillary lymph-nodes, lymphatic and vascular invasion, choice of adjuvant/neoadjuvant chemotherapy, family history of cancer has a statistically significant effect on DFS. Increase in density of lymphocyte infiltration of tumor has also better a prognostic effect on DFS (p=0.02). In multivariate-analysis, only tumor size and choice of adjuvant/neoadjuvant chemotherapy are found to have statistically significant effect.

Conclusion

Tumor lymphocyte infiltration was found to have a statistically significant better prognostic effect on DFS but not on OS of patients with operated TNBC. This result can be due to variability of therapies administered after recurrence and other confounding factors that may have an effect on OS.

Dawn of Monitoring Regulatory T Cells in (Pre-)clinical Studies: Their Relevance Is Slowly Recognised

Regulatory T cells (Tregs) have a prominent role in the control of immune homeostasis. Pharmacological impact on their activity or balance with effector T cells could contribute to (impaired) clinical responses or adverse events. Monitoring treatment-related effects on T cell subsets may therefore be part of (pre-)clinical studies for medicinal products. However, the extent of immune monitoring performed in studies for marketing authorisation and the degree of correspondence with data available in the public domain is not known. We evaluated the presence of T cell immunomonitoring in 46 registration dossiers of monoclonal antibodies indicated for immune-related disorders and published scientific papers. We found that the depth of Treg analysis in registration dossiers was rather small. Nevertheless, data on treatment-related Treg effects are available in public academia-driven studies (post-registration) and suggest that Tregs may act as a biomarker for clinical responses. However, public data are fragmented and obtained with heterogeneity of experimental approaches from a diversity of species and tissues. To reveal the potential added value of T cell (and particular Treg) evaluation in (pre-)clinical studies, more cell-specific data should be acquired, at least for medicinal products with an immunomodulatory mechanism. Therefore, extensive analysis of T cell subset contribution to clinical responses and the relevance of treatment-induced changes in their levels is needed. Preferably, industry and academia should work together to obtain these data in a standardised manner and to enrich our knowledge about T cell activity in disease pathogenesis and therapies. This will ultimately elucidate the necessity of T cell subset monitoring in the therapeutic benefit-risk assessment.

Functional Blockade of E-Selectin in Tumor-Associated Vessels Enhances Anti-Tumor Effect of Doxorubicin in Breast Cancer

Chemotherapy is a mainstay of treatment for solid tumors. However, little is known about how therapy-induced immune cell infiltration may affect therapy response. We found substantial CD45⁺ immune cell density adjacent to E-selectin expressing inflamed vessels in doxorubicin (DOX)-treated residual human breast tumors. While CD45 level was significantly elevated in DOX-treated wildtype mice, it remained unchanged in DOX-treated tumors from E-selectin null mice. Similarly, intravenous administration of anti-E-selectin aptamer (ESTA) resulted in a significant reduction in CD45⁺ immune cell density in DOX-treated residual tumors, which coincided with a delay in tumor growth and lung metastasis in MMTV-pyMT mice. Additionally, both tumor infiltrating T-lymphocytes and tumor associated-macrophages were skewed towards T_H2 in DOX-treated residual breast tumors; however, ESTA suppressed these changes. This study suggests that DOX treatment instigates de novo intratumoral infiltration of immune cells through E-selectin, and functional blockade of E-selectin may reduce residual tumor burden as well as metastasis through suppression of T_H2 shift.

Changes in DNA Damage Response Markers with Treatment in Advanced Ovarian Cancer

Ovarian cancer (OC) is sensitive to upfront chemotherapy, which is likely attributable to defects in DNA damage repair (DDR). Unfortunately, patients relapse and the evolution of DDR competency are poorly described. We examined the expression of proposed effectors in homologous recombination (HR: RAD51, ATM, FANCD2), error-prone non-homologous end-joining (NHEJ: 53BP1), and base excision repair pathways (BER: PAR and PARP1) in a cohort of sequential OC samples obtained at diagnosis, after neoadjuvant chemotherapy (NACT), and/or at relapse from a total of 147 patients. Immunohistochemical (IHC) expression was quantified using the H-score (0-300), where H ≤ 10 defined negativity. Before NACT, a significant number of cases lacked the expression of some effectors: 60%, 60%, and 24% were PAR-, FANCD2-, or RAD51-negative, with a reassuringly similar proportion of negative biomarkers after NACT. In multivariate analysis, there was a poorer progression-free survival (PFS) and overall survival (OS) for cases with competent HR at diagnosis (PRE-NACT 53BP1-/RAD51+, hazard ratio (HR) 3.13, p = 0.009 and HR 2.78, p = 0.024) and after NACT (POST-NACT FANCD2+/RAD51+ HR 1.89, p = 0.05 and HR 2.38, p = 0.02; POST-NACT PARP-1+/RAD51+ HR 1.79, p = 0.038 and HR 2.04, p = 0.034), reflecting proficient DNA repair. Overall, HR-competent tumors appeared to have a dismal prognosis in comparison with tumors utilizing NHEJ, as assessed either at baseline or post-NACT. Accurate knowledge of the HR status during treatment is clinically important for the efficient timing of platinum-based and targeted therapies with poly(ADP-ribose) polymerase inhibitors (PARPi).

Prognostic role of tumor-infiltrating lymphocytes in gastric cancer: a meta-analysis and experimental validation

INTRODUCTION

We performed a meta-analysis and an experimental validation to investigate the association between tumor infiltrating lymphocytes (TILs) and the outcome of gastric cancer (GC) patients to provide prognostic indicators for clinical practice.

MATERIAL AND METHODS

The relative literature of TILs in tumor tissue from patients with gastric cancer was searched from PubMed, Embase, NIH databases, from April 2000 to 31 December 2016. Studies on the prognostic value of TILs as CD3+, CD4+, CD8+, GrB+, and FOXP3+ lymphocytes for GC were retrieved, and also the related references were traced as supplements. Independent screening documents, extracting information and evaluating quality were implemented independently by 2 evaluators according to the inclusion and exclusion criteria, which were then analyzed by meta-analysis using STATA version 12.0 software.

RESULTS

The results indicated that high levels of intratumoral CD8+, CD3+ and CD4+ T cell infiltration were associated with better overall survival(OS) in gastric cancer patients, while high density of intratumoral FOXP3+ T cells was not closely associated with a worse outcome. Additionally, in our study, higher density of granzyme B+ (GrB+) T cell infiltration indicated an optimistic prognosis, and infiltration of a larger number of general TILs also suggested a favorable prognosis by log-rank test analysis.

CONCLUSIONS

This meta-analysis clarified that high levels of CD8+, CD3+, and CD4+ T cell infiltration in tumor tissue showed better OS in GC patients, whereas high density of FOXP3+ T cell infiltration may not be recognized as a negative prognostic factor. These results may provide some useful prognostic indicators for clinical application in gastric cancer.

Increased Stromal Infiltrating Lymphocytes are Associated with Circulating Tumor Cells and Metastatic Relapse in Breast Cancer Patients After Neoadjuvant Chemotherapy

Background

Circulating tumor cells (CTCs) intravasate into the bloodstream throughout early cancer stages, promoting metastasis. The tumor microenvironment plays a crucial role in disease progression and outcome. The aim of this prospective study was to investigate the associations of intratumoral and stromal tumor-infiltrating lymphocytes (TILs) with CTCs among patients receiving neoadjuvant chemotherapy (NAC).

Methods

We analyzed CTCs in 30 patients with primary breast cancer before and after NAC. The numbers of intratumoral TILs (iTILs) and stromal TILs (sTILs) from pre-NAC formalin-fixed paraffin-embedded core biopsies and post-NAC surgical samples were analyzed. The associations of TILs with pathologic complete response (pCR) and outcome were also evaluated.

Results

Of the 30 patients, pCR was achieved in nine (30.0%) patients. A total of 25 (83.3%) patients were CTC-positive before NAC, and eight (26.7%) patients were CTC-positive after NAC. Neither CTC detection before NAC nor CTC after NAC was predictive of pCR. Nevertheless, the presence of CTCs after NAC was significantly associated with early metastatic relapse (P = 0.049) and worse disease-free survival (P = 0.009). After NAC, total sTILs, CD4⁺ T cells, and CD8⁺ T cells were significantly correlated with CTC detection. Increased infiltration of sTILs and CD4⁺ T cells was also an unfavorable prognostic factor as measured by the rate of metastatic relapse.

Conclusion

Detection of CTCs after NAC was positively associated with the metastatic relapse of breast cancer patients. Increased infiltration of sTILs after NAC was correlated with CTCs and was found to be an unfavorable prognostic factor.

Stromal Cell Signature Associated with Response to Neoadjuvant Chemotherapy in Locally Advanced Breast Cancer

Breast cancer stromal compartment, may influence responsiveness to chemotherapy. Our aim was to detect a stromal cell signature (using a direct approach of microdissected stromal cells) associated with response to neoadjuvant chemotherapy (neoCT) in locally advanced breast cancer (LABC). The tumor samples were collected from 44 patients with LABC (29 estrogen receptor (ER) positive and 15 ER negative) before the start of any treatment. Neoadjuvant chemotherapy consisted of doxorubicin and cyclophosphamide, followed by paclitaxel. Response was defined as downstaging to maximum ypT1a-b/ypN0. The stromal cells, mainly composed of fibroblast and immune cells, were microdissected from fresh frozen tumor samples and gene expression profile was determined using Agilent SurePrint G3 Human Gene Expression microarrays. Expression levels were compared using MeV (MultiExperiment Viewer) software, applying SAM (significance analysis of microarrays). To classify samples according to tumor response, the order of median based on confidence statements (MedOr) was used, and to identify gene sets correlated with the phenotype downstaging, gene set enrichment analysis (GSEA). Nine patients presented disease downstaging. Eleven sequences (FDR 17) were differentially expressed, all of which (except H2AFJ) more expressed in responsive tumors, including PTCHD1 and genes involved in abnormal cytotoxic T cell physiology, TOX, LY75, and SH2D1A. The following four pairs of markers could correctly classify all tumor samples according to response: PTCHD1/PDXDC2P, LOC100506731/NEURL4, SH2D1A/ENST00000478672, and TOX/H2AFJ. Gene sets correlated with tumor downstaging (FDR < 0.01) were mainly involved in immune response or lymphocyte activation, including CD47, LCK, NCK1, CD24, CD3E, ZAP70, FOXP3, and CD74, among others. In locally advanced breast cancer, stromal cells may present specific features of immune response that may be associated with chemotherapy response.

Neutrophil-lymphocyte ratio in metastatic breast cancer is not an independent predictor of survival, but depends on other variables

The prognostic impact of neutrophil-lymphocyte ratio (NLR) in metastatic breast cancer (MBC) has been previously evaluated in early and metastatic mixed breast cancer cohorts or without considering other relevant prognostic factors. Our aim was to determine whether NLR prognostic and predictive value in MBC was dependent on other clinical variables. We studied a consecutive retrospective cohort of patients with MBC from a single centre, with any type of first line systemic treatment. The association of NLR at diagnosis of metastasis with progression free survival (PFS) and overall survival (OS) was evaluated using Cox univariate and multivariate proportional hazard models. In the full cohort, that included 263 MBC patients, a higher than the median (>2.32) NLR was significantly associated with OS in the univariate analysis (HR 1.36, 95% CI 1.00–1.83), but the association was non-significant (HR 1.12, 95% CI 0.80–1.56) when other clinical covariates (performance status, stage at diagnosis, CNS involvement, visceral disease and visceral crisis) were included in the multivariate analysis. No significant association was observed for PFS. In conclusion, MBC patients with higher baseline NLR had worse overall survival, but the prognostic impact of NLR is likely derived from its association with other relevant clinical prognostic factors.

Influence of mutagenic versus non-mutagenic pre-operative chemotherapy on the immune infiltration of residual breast cancer

Background: Chemotherapeutic agents are often mutagenic. Induction of mutation associated neo-epitopes is one of the mechanisms by which chemotherapy is thought to increase the number of tumor-infiltrating lymphocytes. It is not known, however, whether treatment with various chemotherapeutic agents with different mutagenic capacity induce a significantly different number of stromal tumor-infiltrating lymphocytes (StrTIL) in residual cancer.Methods: One hundred and twenty breast carcinoma cases with residual disease that were treated with one of three types of pre-operative chemotherapy regimens were selected for the study. The percentage of StrTIL was evaluated in pretreatment core biopsies (pre-StrTIL) and post-treatment surgical tumor samples (post-StrTIL). TIL changes (ΔStrTIL) were calculated from the difference between post-StrTIL and pre-StrTIL.Results: When analyzing the pre-StrTIL and post-StrTIL among the three treatment groups, we detected significant StrTIL increase independently of the treatment applied. Based on distant metastases-free survival analysis, both post-StrTIL and ΔStrTIL was found to be independent prognostic factor in HR negative cases. Conclusions: Significant increase of StrTIL in the residual disease was observed in patients treated with the highly (platinum), moderately (cyclophosphamide) and marginally mutagenic chemotherapeutic agents (taxane, anthracycline). Increase in StrTIL in residual cancer compared to pretreatment tumor tissue is associated with improved distant metastasis-free survival in cases with HR negative breast carcinoma.

Evaluation of the Predictive Role of Tumor Immune Infiltrate in Patients with HER2-Positive Breast Cancer Treated with Neoadjuvant Anti-HER2 Therapy without Chemotherapy

PURPOSE

Tumor-infiltrating lymphocytes (TIL) are associated with benefit to trastuzumab and chemotherapy in patients with early-stage HER2⁺ breast cancer. The predictive value of TILs, TIL subsets, and other immune cells in patients receiving chemotherapy-sparing lapatinib plus trastuzumab treatment is unclear.Experimental Design: Hematoxylin and eosin-stained slides (n = 59) were used to score stromal (s-)TILs from pretreatment biopsies of patients enrolled in the neoadjuvant TBCRC006 trial of 12-week lapatinib plus trastuzumab therapy (plus endocrine therapy for ER⁺ tumors). A 60% threshold was used to define lymphocyte-predominant breast cancer (LPBC). Multiplexed immunofluorescence (m-IF) staining (CD4, CD8, CD20, CD68, and FoxP3) and multispectral imaging were performed to characterize immune infiltrates in single formalin-fixed paraffin-embedded slides (n = 33).

RESULTS

The pathologic complete response (pCR) rate was numerically higher in patients with LPBC compared with patients with non-LPBC (50% vs. 19%, P = 0.057). Unsupervised hierarchical clustering of the five immune markers identified two patient clusters with different responses to lapatinib plus trastuzumab treatment (pCR = 7% vs. 50%, for cluster 1 vs. 2 respectively; P = 0.01). In multivariable analysis, cluster 2, characterized by high CD4⁺, CD8⁺, CD20⁺ s-TILs, and high CD20⁺ intratumoral TILs, was independently associated with a higher pCR rate (P = 0.03). Analysis of single immune subpopulations revealed a significant association of pCR with higher baseline infiltration by s-CD4, intratumoral (i-) CD4, and i-CD20⁺ TILs.

CONCLUSIONS

LPBC was marginally associated with higher pCR rate than non-LPBC in patients with lapatinib plus trastuzumab treated HER2⁺ breast cancer. Quantitative assessment of the immune infiltrate by m-IF is feasible and may help correlate individual immune cell subpopulations and immune cell profiles with treatment response.

Multi-omics analysis of tumor mutation burden combined with immune infiltrates in bladder urothelial carcinoma

To explore the prognosis of tumor mutation burden (TMB) and underlying relationships with tumor-infiltrating immune cells in bladder cancer (BLCA). Transcriptome profiles and somatic mutation data from The Cancer Genome Atlas database by the GDC tool. A total of 437 samples were included, consisted of 412 BLCA patients and matched 25 normal samples. Specific mutation information was summarized and illustrated in waterfall plot. Higher TMB levels revealed improved overall survival (OS) and lower tumor recurrence. We found 68 differentially expressed genes in two TMB groups and identified eight independent hub TMB-related signature. Pathway analysis suggested that differential TMB-related signature correlated with multiple cancer-related crosstalk, including cell cycle, DNA replication, cellular senescence, and p53 signaling pathway. Besides, the tumor mutation burden related signature (TMBRS) model based on eight signature possessed well predictive value with area under curve (AUC) = 0.753, and patients with higher TMBRS scores showed worse OS outcomes (p < .001). Moreover, we exhibited the inferred immune cell fractions in box plot and differential abundance of immune cells were shown in the heatmap. The Wilcoxon rank-sum test suggested that CD8+ T cell (p = .001) and memory activated CD4+ T cell (p = .004) showed higher infiltrating levels in high-TMB group, while the density of resting mast cells showed lower infiltrating level in high-TMB group (p = .016). Finally, it is significant to note that CD8+ T cell and memory activated CD4+ T cell subsets not only revealed higher infiltrating abundance in high-TMB group but correlated with prolonged OS and lower risk of tumor recurrence, respectively.

Nutritional, immunological and antioxidant defense status of outpatients diagnosed with colorectal cancer - a case-control study of the little-studied population

This cross-sectional study was conducted to investigate nutritional and immunological status of colorectal cancer (CRC) patients in a little-studied population from developing country, Pakistan. Data on 81 CRC patients and 37 healthy controls (HCs) were collected on nutritional status, nutrient intake, percent body fat (%BF), selected immunological parameters, phytochemical index (PI), healthy eating index (HEI), and prognostic nutrition index (PNI). Blood samples were used for immunological and antiradical defense potential (expressed as 50% hemolysis time; HT₅₀). Results show 40/81 (49.4%) patients reported weight loss in past 3-6 mo, Significant differences were found in HEI values between patients vs. HCs, and between patients in low vs. high PNI groups (P, for all trends <0.05). Patients in the higher PNI group were heavier, had higher % BF, higher energy intake, and higher PI score as compared to patients in the low PNI group (P < 0.05). Low PNI was positively associated with non-significantly lower CD4:CD8 ratios, higher B-cells and NK cells (P, for all trends >0.05), but with significantly higher hs-CRP levels, and lower HT₅₀ values (P, for all trends <0.001). In conclusion, CRC patients in a little-studied population have compromised nutritional and immunological health with lower HEI and PNI scores.

Prognostic impact of tumor-associated immune cell infiltrates at radical cystectomy for bladder cancer

OBJECTIVES

To assess whether the presence and location of tumor-associated immune cell infiltrates (TAIC) on histological slides obtained from cystectomy specimens impacts on oncological outcomes of patients with bladder cancer (BC).

MATERIAL AND METHODS

A total of 320 consecutive patients staged with cM0 bladder cancer underwent radical cystectomy (RC) between 2004 and 2013. The presence of TAIC (either located peritumorally [PIC] and/or intratumorally [IIC]) on histological slides was retrospectively assessed and correlated with outcomes. Kaplan-Meier analyses were used to estimate the impact of TAIC on recurrence-free (RFS), cancer-specific (CSS), and overall survival (OS). Multivariable Cox-regression analysis was carried out to evaluate risk factors of recurrence. The median follow-up was 37 months (IQR: 10-55).

RESULTS

Of the 320 patients, 42 (13.1%) exhibited IIC, 141 (44.1%) PIC and 137 (42.8%) no TAIC in the cystectomy specimens. Absence of TAIC was associated with higher ECOG performance status (P = 0.042), histologically advanced tumor stage (≥pT3a; P < 0.001), lymph node tumor involvement (pN+; P = 0.022), positive soft tissue surgical margins (P = 0.006), lymphovascular invasion (P < 0.001), and elevated serum C-reactive protein levels (P < 0.001). The rate of never smokers was significantly higher in the IIC-group (64.3%) compared to the PIC-group (39.7%, P = 0.007) and those without TAIC (35.8%, P = 0.001). The 3-year RFS/CSS/OS was 73.9%/88.5%/76.7% for patients with IIC, 69.4%/85.2%/70.1% for PIC and 47.6%/68.5%/56.1% for patients without TAIC (P < 0.001/<0.001/0.001 for TAIC vs. no TAIC). In multivariable analysis, adjusted for all significant parameters of univariable analysis, histologically advanced tumor stage (P = 0.003), node-positive disease (P = 0.002), and the absence of TAIC (P = 0.035) were independent prognosticators for recurrence.

CONCLUSIONS

In this analysis, the presence and location of TAIC in cystectomy specimens was a strong prognosticator for RFS after RC. This finding suggests that the capability of immune cells to migrate into the tumor at the time of RC is prognostically important in invasive bladder cancer.

Residual cancer burden index and tumor-infiltrating lymphocyte subtypes in triple-negative breast cancer after neoadjuvant chemotherapy

PURPOSE

There is a need to refine the prognosis of triple-negative breast cancer (TNBC) patients after neoadjuvant chemotherapy (NAC) and to study the influence of the tumor microenvironment. We evaluated the prognostic value of pathological and immune markers in TNBC with residual disease (RD) after NAC.

METHODS

In a series of 186 TNBC patients treated by NAC, we assessed the prognostic value of the Residual Cancer Burden (RCB) index. In 109 patients with RD, we studied the impact of clinicopathological features and tumor immune response in the residual tumor on overall survival (OS) and distant recurrence-free interval (DRFI).

RESULTS

In the whole group, the OS and DRFI, at 3 years, were statistically different between the different classes of RCB (P = 0.0004 and P < 0.0001, respectively). In univariate analysis of the RD group, low RCB index and high ratios of stromal tumor-infiltrating lymphocytes (TILs), CD3 + TILs, CD4 + TILs, CD8 + TILs, and IDO1-positive cells were significant favorable prognostic factors for DRFI at 3 years. In the final multivariate model, CD4 + TILs and RCB index showed a statistically independent prognostic significance for DRFI [Hazard Ratio (HR) 2.88 (95%CI 1.34-6.17), P = 0.007 and HR 12.04 (95%CI 2.78-52.23, P < 0.0001), respectively]. The CD4 + TIL levels influenced survival in the different RCB classes with a significant effect observed in RCB-II and RCB-III classes (P = 0.05 and P = 0.05, respectively).

CONCLUSIONS

These results suggest that the combination of pathological (RCB index) and tumor micro-environmental features (CD4 + TILs) help refining the prognosis of TNBC patients with RD following NAC.

Interaction between Molecular Subtypes and Stromal Immune Infiltration before and after Treatment in Breast Cancer Patients Treated with Neoadjuvant Chemotherapy

PURPOSE

High levels of tumor-infiltrating lymphocytes (TIL) before neoadjuvant chemotherapy (NAC) are associated with higher pathologic complete response (pCR) rates and better survival in triple-negative breast cancer (TNBC) and HER2-positive breast cancer. We investigated the value of TIL levels by evaluating lymphocyte infiltration before and after NAC.

EXPERIMENTAL DESIGN

We assessed stromal TIL levels in 716 pre- and posttreatment matched paired specimens, according to the guidelines of the International TIL Working Group.

RESULTS

Pre-NAC TIL levels were higher in tumors for which pCR was achieved than in cases with residual disease (33.9% vs. 20.3%, P = 0.001). This was observed in luminal tumors and TNBCs, but not in HER2-positive breast cancers (P _Interaction = 0.001). The association between pre-NAC TIL levels and pCR was nonlinear in TNBCs (P = 0.005). Mean TIL levels decreased after chemotherapy completion (pre-NAC TILs: 24.1% vs. post-NAC TILs: 13.0%, P < 0.001). This decrease was strongly associated with high pCR rates, and the variation of TIL levels was strongly inversely correlated with pre-NAC TIL levels (r = -0.80, P < 0.001). Pre-NAC TILs and disease-free survival (DFS) were associated in a nonlinear manner (P < 0.001). High post-NAC TIL levels were associated with aggressive tumor characteristics and with impaired DFS in HER2-positive breast cancers (HR, 1.04; confidence interval, 1.02-1.06; P = 0.001), but not in luminal tumors or TNBCs (P _Interaction = 0.04).

CONCLUSIONS

The associations of pre- and post-NAC TIL levels with response to treatment and DFS differ between breast cancer subtypes. The characterization of immune subpopulations may improve our understanding of the complex interactions between pre- or post-NAC setting, breast cancer subtype, response to treatment, and prognosis.

An immune infiltration signature to predict the overall survival of patients with colon cancer

Immune infiltration of tumors has been increasingly accepted as a prognostic factor in colon cancer. Here, we aim to develop a novel immune signature, based on estimated immune landscape from tumor transcriptomes, to predict the overall survival of patients with colon cancer. The compositions of 22 immune cell subtypes from three microarray datasets were characterized with the CIBERSORT deconvolution algorithm. A prognostic immunoscore (PIS) model for overall survival prediction was established by using least absolute shrinkage and selection operator (LASSO) penalized regression analysis. A total of 17 immune cell markers were screened out in the LASSO model and were then aggregated to generate the PIS. In the training cohort (n = 490), patients with high PIS exhibited a remarkably poorer overall survival than those with low PIS. Similar results were obtained in patients with different TNM stages and in patients receiving adjunctive chemotherapy or not. Multivariate Cox regression indicated that the PIS was an independent predictor for overall survival in colon cancer (hazard ratio: 2.734, 95% confidence interval: 2.052-3.643, p < .001). The prognostic capability of PIS was also confirmed in the testing cohort (n = 245) and the entire cohort (n = 735). As for biological implications, the PIS was significantly associated with some immune checkpoints, inflammatory factors, epithelial-mesenchymal transformation regulators, and many known signaling pathways in cancer. The results of our study provide a novel and promising immune signature for overall survival prediction of patients with colon cancer.

Cancer immunoediting and resistance to T cell-based immunotherapy

Anticancer immunotherapies involving the use of immune-checkpoint inhibitors or adoptive cellular transfer have emerged as new therapeutic pillars within oncology. These treatments function by overcoming or relieving tumour-induced immunosuppression, thereby enabling immune-mediated tumour clearance. While often more effective and better tolerated than traditional and targeted therapies, many patients have innate or acquired resistance to immunotherapies. Cancer immunoediting is the process whereby the immune system can both constrain and promote tumour development, which proceeds through three phases termed elimination, equilibrium and escape. Throughout these phases, tumour immunogenicity is edited, and immunosuppressive mechanisms that enable disease progression are acquired. The mechanisms of resistance to immunotherapy seem to broadly overlap with those used by cancers as they undergo immunoediting to evade detection by the immune system. In this Review, we discuss how a deeper understanding of the mechanisms underlying the cancer immunoediting process can provide insight into the development of resistance to immunotherapies and the strategies that can be used to overcome such resistance.

Evaluation of Breast and Axillary Lymph Node Specimens in Breast Cancer Patients Treated With Neoadjuvant Systemic Therapy

Breast and axillary lymph node specimens from breast cancer patients treated with neoadjuvant systemic therapy are being encountered by pathologists with increasing frequency. Evaluation of these specimens presents challenges that differ from those encountered during the examination of other types of breast specimens. This article reviews the key issues regarding the gross and microscopic evaluation of post-neoadjuvant systemic therapy breast and lymph node specimens, and emphasizes the importance of accurate specimen evaluation in assessing treatment response.

Expression of the immune checkpoint receptor TIGIT in seminoma

A characteristic feature of testicular seminoma is the abundance of immune cells in the tumor microenvironment, raising the possibility that immune checkpoint inhibitors may serve as a therapeutic option in these types of tumors. T cell immunoreceptor with Ig and ITIM domains (TIGIT) is an inhibitory immune checkpoint receptor in analogy to PD-1, and drugs targeting TIGIT are currently being investigated in clinical trials. Little is known about the expression of these proteins in testicular seminomas. Therefore the present study performed immunohistochemical analysis to determine the relative abundance of TIGIT and PD-1 in relation to the total CD3⁺ immune cell infiltration in a tissue microarray (TMA) constructed from 78 seminoma patients. The fraction of TIGIT⁺ and PD-1⁺ lymphocytes was highly variable in individual cancers and ranged from 2.3 to 69.4% (mean: 32.2±14.7%) for TIGIT and from 0.8 to 56.5% (mean: 21.6±13.2%) for PD-1. The same high degree of variability was also identified for the ratio of PD-1 to TIGIT positive cells, which varied from a dominance of TIGIT (PD-1: TIGIT ratio=0.02) in 74% of patients, to a predominance of PD-1 (PD-1: TIGIT ratio=12.5) in 23% of patients. In summary, the immune checkpoint receptors TIGIT and PD-1 are abundantly expressed in human seminomas. Once available, anti-TIGIT antibodies, possibly in combination with anti-PD-1 drugs, may be a reasonable therapeutic strategy for this type of cancer.