Tissue eosinophilia correlates strongly with poor prognosis in nodular sclerosing Hodgkin's disease, allowing for known prognostic factors

Eosinophilic granulocytes as a potential prognostic marker for cancer progression and therapeutic response in malignant melanoma

The importance of eosinophilic granulocytes in cancer has been widely discussed in recent years. The current study reviews the evidence on the role of eosinophilic granulocytes in melanoma as a prognostic marker for cancer progression and the efficacy of treatment with modern immune checkpoint inhibitors. A total of 33 human clinical studies were included in the review, with heterogeneous data due to differences in patients populations, study design and inclusion of small study groups. However, 28 of the 33 studies suggested that eosinophilic granulocytes could be used as a prognostic biomarker for outcome and/or potential response to systemic treatment and/or occurrence of adverse events in melanoma patients. Nevertheless, the exact role of eosinophils remains to be elucidated. Further prospective, larger and better controlled studies are warranted to clarify the significance of eosinophilic granulocytes in patients with melanoma, in more details.

Neutrophil-to-lymphocyte ratio and monocyte-to-eosinophil ratio as prognostic indicators for advanced nasopharyngeal carcinoma

OBJECTIVE

To determine the predictive value of the neutrophil-to-lymphocyte ratio (NLR), lymphocyte-to-monocyte ratio (LMR), neutrophil-to-eosinophil ratio (NER), lymphocyte-to-eosinophil ratio (LER), monocyte-to-eosinophil ratio (MER), systemic inflammatory response index (SIRI), and ratio of inflammatory cells before and after treatment for predicting survival in advanced nasopharyngeal carcinoma (NPC) and to provide a reference for treatment.

METHODS

A retrospective review of 70 patients was performed. Serological indexes were obtained by drawing blood before and after systemic therapy. The cutoff values of these indexes were determined by receiver operating characteristic (ROC) curves. The prognostic value of the indexes for overall survival (OS) and distant metastasis free survival (DMFS) was evaluated.

RESULTS

Survival analysis showed that a smaller pretreatment LMR value was associated with poor OS; larger pretreatment NER, LER, MER, and SIRI values were associated with poor OS; a smaller posttreatment LMR value was associated with poor OS; larger posttreatment NLR, NER, MER, and SIRI values were associated with poor OS; a smaller pretreatment LMR value was associated with poor DMFS; larger pretreatment NLR, NER, LER, and MER values were associated with poor DMFS; and larger posttreatment NLR, NER, LER, and MER values were associated with poor DMFS. Furthermore, a larger neutrophil after treatment-to-neutrophil before treatment ratio was associated with poor OS and DMFS. Logistic regression analysis showed that pretreatment MER and posttreatment NLR were independent predictors of OS in patients with advanced NPC; moreover, pretreatment and posttreatment MER and NLR were independent prognostic factors for DMFS in patients with advanced NPC.

CONCLUSIONS

The NLR, NER and MER can be used to predict survival in advanced NPC patients. Eosinophils might be one of the factors for the good prognosis of NPC patients. In addition, an increased number of neutrophils after treatment may indicate a favorable prognosis.

An increased relative eosinophil count as a predictive dynamic biomarker in non-small cell lung cancer patients treated with immune checkpoint inhibitors

BACKGROUND

An increased relative eosinophil count (REC) has potential as a predictive biomarker for a beneficial clinical response and outcome to cancer immunotherapies. Therefore, the present study investigated the impact of an increased posttreatment REC on the prognosis of non-small cell lung cancer (NSCLC) patients treated with immune checkpoint inhibitors (ICIs).

METHODS

We retrospectively reviewed all 151 patients diagnosed with NSCLC and treated with ICI monotherapy and blood test data between March 2016 and August 2021 at National Hospital Organization Kochi Hospital and Tokushima University.

RESULTS

A total of 151 patients with a mean age of 69 years were included. REC after 4 weeks of initial ICI monotherapy was higher than pretreatment REC in 87 patients but not in 64. REC after 4 weeks of the ICI treatment with and without an increased REC were 4.4 and 1.8%, respectively (p < 0.001). Disease control rates (DCR) were significantly higher in patients with than in those without an increased REC (84% vs. 47%, p < 0.001). The median overall survival (OS) of lung cancer patients with or without an increased REC were 674 and 234 days, respectively. A Kaplan-Meier univariate analysis revealed a significant difference in OS between the two groups (p < 0.001). A Cox proportional regression analysis identified an increased REC as an independent predictor of OS (p = 0.003).

CONCLUSION

ICI-treated NSCLC patients with an increased REC after 4 weeks of treatment had a better DCR and prognosis than the other patients examined.

Exploiting innate immunity for cancer immunotherapy

Immunotherapies have revolutionized the treatment paradigms of various types of cancers. However, most of these immunomodulatory strategies focus on harnessing adaptive immunity, mainly by inhibiting immunosuppressive signaling with immune checkpoint blockade, or enhancing immunostimulatory signaling with bispecific T cell engager and chimeric antigen receptor (CAR)-T cell. Although these agents have already achieved great success, only a tiny percentage of patients could benefit from immunotherapies. Actually, immunotherapy efficacy is determined by multiple components in the tumor microenvironment beyond adaptive immunity. Cells from the innate arm of the immune system, such as macrophages, dendritic cells, myeloid-derived suppressor cells, neutrophils, natural killer cells, and unconventional T cells, also participate in cancer immune evasion and surveillance. Considering that the innate arm is the cornerstone of the antitumor immune response, utilizing innate immunity provides potential therapeutic options for cancer control. Up to now, strategies exploiting innate immunity, such as agonists of stimulator of interferon genes, CAR-macrophage or -natural killer cell therapies, metabolic regulators, and novel immune checkpoint blockade, have exhibited potent antitumor activities in preclinical and clinical studies. Here, we summarize the latest insights into the potential roles of innate cells in antitumor immunity and discuss the advances in innate arm-targeted therapeutic strategies.

Eosinophils in metastatic melanoma

The potential significance of tissue eosinophils melanomas is unknown. We strove to determine a potential association between the presence of tissue eosinophils and prognosis of patients with metastatic melanoma (MM). A retrospective electronic data base was queried to identify patients (age ≥18 years) evaluated January 1, 2011-October 1, 2022 (inclusive) at our multi-site medical center, who had metastatic melanoma and at least 1 biopsy of melanoma or a melanocytic nevus that was reported to show eosinophils. Patient demographics, histopathological tumor features, AJCC classification parameters, and peripheral blood eosinophilia (PBE) obtained during the patients' routine care were recorded. Seven patients met inclusion criteria had checkpoint inhibitor therapy for MM; 4/7 had prominent eosinophil infiltrates among their melanocytic nevi or/and melanomas, and all had absent or less than predicted tumor progression. In our small cohort of patients undergoing immunotherapy for metastatic melanoma, the presence of tissue eosinophils among nevi or melanomas was associated with a favorable response. While lymphocytes have been considered key in the host response to melanoma, the role of eosinophils may be underappreciated.

Pretreatment eosinophil counts as a predictive biomarker in non-small cell lung cancer patients treated with immune checkpoint inhibitors

BACKGROUND

The peripheral blood eosinophil count prior to treatment has potential as a predictive biomarker for a beneficial clinical response to cancer immunotherapies. Therefore, the present study investigated the impact of the eosinophil count on overall survival (OS) in non-small cell lung cancer (NSCLC) patients treated with immune checkpoint inhibitors (ICI).

METHODS

We retrospectively reviewed all patients diagnosed with NSCLC and treated with ICI monotherapy between March 2016 and August 2021 at National Hospital Organization Kochi Hospital and Tokushima University.

RESULTS

A total of 166 patients were included. Fifty-five patients had an eosinophil count of less than 100 cells/μL (Eo < 100). Nighty-eight patients had an eosinophil count of 100 cells/μL or more, but less than 500 cells/μL (100 ≤ Eo < 500). Thirteen patients had an eosinophil count of 500 cells/μL or more (Eo ≥500). The median OS of all lung cancer patients was 476 days. The median OS of lung cancer patients with Eo <100, 100 ≤ Eo <500, and Eo ≥500 was 339, 667, and 143 days, respectively. A Kaplan-Meier univariate analysis showed a significant difference in OS between these three groups (p < 0.001). A Cox proportional regression analysis identified 100 ≤ Eo <500 (p = 0.04), ECOG PS score ≥ 2 (p = 0.02), tumor size ≥5 cm (p = 0.02), and PD-L1 ≥ 1% (p = 0.01) as independent predictors of OS.

CONCLUSION

OS was significantly longer in ICI-treated NSCLC patients with a pretreatment eosinophil count of 100 ≤ Eo <500 than in the other patients and, thus, has potential as a new predictive biomarker.

Eosinophils Exert Antitumorigenic Effects in the Development of Esophageal Squamous Cell Carcinoma

BACKGROUND AND AIMS

Eosinophils are present in several solid tumors and have context-dependent function. Our aim is to define the contribution of eosinophils in esophageal squamous cell carcinoma (ESCC), as their role in ESCC is unknown.

METHODS

Eosinophils were enumerated in tissues from 2 ESCC cohorts. Mice were treated with 4-NQO for 8 weeks to induce precancer or 16 weeks to induce carcinoma. The eosinophil number was modified by a monoclonal antibody to interleukin-5 (IL5mAb), recombinant IL-5 (rIL-5), or genetically with eosinophil-deficient (ΔdblGATA) mice or mice deficient in eosinophil chemoattractant eotaxin-1 (Ccl11-/-). Esophageal tissue and eosinophil-specific RNA sequencing was performed to understand eosinophil function. Three-dimensional coculturing of eosinophils with precancer or cancer cells was done to ascertain direct effects of eosinophils.

RESULTS

Activated eosinophils are present in higher numbers in early-stage vs late-stage ESCC. Mice treated with 4-NQO exhibit more esophageal eosinophils in precancer vs cancer. Correspondingly, epithelial cell Ccl11 expression is higher in mice with precancer. Eosinophil depletion using 3 mouse models (Ccl11-/- mice, ΔdblGATA mice, IL5mAb treatment) all display exacerbated 4-NQO tumorigenesis. Conversely, treatment with rIL-5 increases esophageal eosinophilia and protects against precancer and carcinoma. Tissue and eosinophil RNA sequencing revealed eosinophils drive oxidative stress in precancer. In vitro coculturing of eosinophils with precancer or cancer cells resulted in increased apoptosis in the presence of a degranulating agent, which is reversed with NAC, a reactive oxygen species scavenger. ΔdblGATA mice exhibited increased CD4 T cell infiltration, IL-17, and enrichment of IL-17 protumorigenic pathways.

CONCLUSION

Eosinophils likely protect against ESCC through reactive oxygen species release during degranulation and suppression of IL-17.

Unraveling the Immune Microenvironment in Classic Hodgkin Lymphoma: Prognostic and Therapeutic Implications

Classic Hodgkin lymphoma (cHL) is a lymphoid neoplasm composed of rare neoplastic Hodgkin and Reed-Sternberg (HRS) cells surrounded by a reactive tumor microenvironment (TME) with suppressive properties against anti-tumor immunity. TME is mainly composed of T cells (CD4 helper, CD8 cytotoxic and regulatory) and tumor-associated macrophages (TAMs), but the impact of these cells on the natural course of the disease is not absolutely understood. TME contributes to the immune evasion of neoplastic HRS cells through the production of various cytokines and/or the aberrant expression of immune checkpoint molecules in ways that have not been fully understood yet. Herein, we present a comprehensive review of findings regarding the cellular components and the molecular features of the immune TME in cHL, its correlation with treatment response and prognosis, as well as the potential targeting of the TME with novel therapies. Among all cells, macrophages appear to be a most appealing target for immunomodulatory therapies, based on their functional plasticity and antitumor potency.

Eosinophils exert direct and indirect anti-tumorigenic effects in the development of esophageal squamous cell carcinoma

Background/Aims

Eosinophils are present in several solid tumors and have context-dependent function. Our aim is to define the contribution of eosinophils in esophageal squamous cell carcinoma (ESCC), since their role in ESCC is unknown.

Methods

Eosinophils were enumerated in tissues from two ESCC cohorts. Mice were treated with 4-nitroquinolone-1-oxide (4-NQO) for 8 weeks to induce pre-cancer or 16 weeks to induce carcinoma. Eosinophil number was modified by monoclonal antibody to IL-5 (IL5mAb), recombinant IL-5 (rIL-5), or genetically with eosinophil-deficient (ΔdblGATA) mice or mice deficient in eosinophil chemoattractant eotaxin-1 ( Ccl11 -/- ). Esophageal tissue and eosinophil specific RNA-sequencing was performed to understand eosinophil function. 3-D co-culturing of eosinophils with pre-cancer or cancer cells was done to ascertain direct effects of eosinophils.

Results

Activated eosinophils are present in higher numbers in early stage versus late stage ESCC. Mice treated with 4-NQO exhibit more esophageal eosinophils in pre-cancer versus cancer. Correspondingly, epithelial cell Ccl11 expression is higher in mice with pre-cancer. Eosinophil depletion using three mouse models ( Ccl11 -/- mice, ΔdblGATA mice, IL5mAb treatment) all display exacerbated 4-NQO tumorigenesis. Conversely, treatment with rIL-5 increases esophageal eosinophilia and protects against pre-cancer and carcinoma. Tissue and eosinophil RNA-sequencing revealed eosinophils drive oxidative stress in pre-cancer. In vitro co-culturing of eosinophils with pre-cancer or cancer cells resulted in increased apoptosis in the presence of a degranulating agent, which is reversed with N-acetylcysteine, a reactive oxygen species (ROS) scavenger. ΔdblGATA mice exhibited increased CD4 T cell infiltration, IL-17, and enrichment of IL-17 pro-tumorigenic pathways.

Conclusion

Eosinophils likely protect against ESCC through ROS release during degranulation and suppression of IL-17.

Tackling the dysregulated immune-checkpoints in classical Hodgkin lymphoma: bidirectional regulations between the microenvironment and Hodgkin/Reed-Sternberg cells

Immune evasion is considered one of the modern hallmarks of cancer and is a key element in the pathogenesis of classical Hodgkin Lymphoma (cHL). This haematological cancer achieves effective avoidance of the host's immune system by overexpressing the PD-L1 and PD-L2 proteins on the surface of the neoplastic cells. Subversion of the PD-1/PD-L axis, however, is not the sole contributor to immune evasion in cHL, as the microenvironment nurtured by the Hodgkin/Reed-Sternberg cells is a major player in the creation of a biological niche that sustains their survival and hinders immune recognition. In this review, we will discuss the physiology of the PD-1/PD-L axis and how cHL is able to exploit a plethora of different molecular mechanisms to build an immunosuppressive microenvironment and achieve optimal immune evasion. We will then discuss the success obtained by checkpoint inhibitors (CPI) in treating cHL, both as single agents and as part of combination strategies, analysing the rationale for their combination with traditional chemotherapeutic compounds and the proposed mechanisms of resistance to CPI immunotherapy.

Eosinophilia in cancer and its regulation by sex hormones

Gender differences in the functionality of the immune system have been attributed, in part, to direct and indirect effects of sex steroids, especially estrogens, on immune cell repertoire and activity. Notable are studies that have defined roles for estrogens in the regulation of the biology of dendritic cells (DCs), macrophages, T cells and natural killer (NK) cells. Although estrogens can modulate eosinophil function, the mechanisms by which this occurs and how it contributes to the pathobiology of different diseases remains underexplored. Furthermore, although the importance of eosinophils in infection is well established, it remains unclear as to how these innate immune cells, which are present in different tumors, impact the biology of cancer cells and/or response to therapeutics. The observation that eosinophilia influences the efficacy of immune checkpoint blockers (ICBs) is significant considering the role of estrogens as regulators of eosinophil function and recent studies suggesting that response to ICBs is impacted by gender. Thus, in this review, we consider what is known about the roles of estrogen(s) in regulating tissue eosinophilia/eosinophil function and how this influences the pathobiology of breast cancer (in particular). This information provides the context for a discussion of how estrogens/the estrogen receptor (ER) signaling axis can be targeted in eosinophils and how this would be expected to influence the activity of standard-of-care interventions and contemporary immunotherapy regimens in cancer(s).

Prognostic impact of peripheral eosinophil counts in patients with diffuse large B-cell lymphoma receiving chimeric antigen receptor T-cell therapy

BACKGROUND AIMS

Chimeric antigen receptor (CAR) T-cell therapy is a breakthrough treatment for patients with relapsed or refractory diffuse large B-cell lymphoma. However, many patients do not achieve remission or relapse after remission. Previous studies have demonstrated that eosinophils have synergistic anti-tumor effects with CD8⁺T cells and pre-CAR T-eosinophil counts are associated with the efficacy of CAR T cells.

METHODS

We retrospectively analyzed the eosinophil counts of patients with diffuse large B-cell lymphoma and found it changed remarkably pre- and post-CAR T-cell therapy.

RESULTS

Patients who achieved complete remission after CAR T-cell infusion had greater post-CAR T-eosinophil counts than those who did not. Kaplan-Meier curves showed that patients with greater eosinophil counts during the second month after CAR T-cell infusion had superior progression-free survival and overall survival compared with those with lower eosinophil counts.

CONCLUSIONS

For patients who responded to CAR T-cell therapy, eosinophil counts also can be used to predict 6-month duration of response. In conclusion, the post-CAR T-eosinophil count is associated with the prognosis of patients treated with CAR T-cell therapy and can be used to clinically identify patients who can achieve longer remission after CAR T-cell infusion.

Predictors of risk of relapse in classic Hodgkin lymphoma

Using multiparametric flow cytometric analysis, in a cohort of 62 patients with classic Hodgkin lymphoma having a median follow-up period of 69.5 months, we found-patients who experienced primary resistance or disease relapse (DR) had lower percentage of rosetted Hodgkin Reed-Sternberg cells (HRS-cells) as compared with patients who achieved sustained complete remission (SCR) (p=0.022); patients >35 years of age had higher percentage of HRS-cells (p=0.017) and lower percentage of B cells (p=0.017) and the nodular sclerosis subtype had higher percentage of B-cells (p=0.046) and activated B-cells (p=0.03). The proportion of SCR and DR subsets did not differ by histological subtypes, disease stage or age groups.

Radiation-induced eosinophil increase ratio predicts patient outcomes in non-small celllung cancer

Background and purpose

Radiotherapy (RT) is a double-edged sword in regulating immune responses. This study aimed to investigate the impact of thoracic RT on circulating eosinophils and its association with patient outcomes in non-small cell lung cancer (NSCLC).

Materials and methods

This retrospective study included 240 patients with advanced NSCLC treated with definitive thoracic RT from January 2012 to January 2020. Statistics included Kaplan-Meier analysis of overall survival (OS) and progression-free survival (PFS), multivariate Cox analyses to identify significant variables, and Spearman’s correlation to qualify the relationship between dose-volume histogram (DVH) parameters and EIR.

Results

Absolute eosinophil counts (AECs) showed an increasing trend during RT and an obvious peak in the 1^st month after RT. Thresholds of eosinophil increase ratio (EIR) at the 1^st month after RT for both OS and PFS were 1.43. Patients with high EIR above 1.43 experienced particularly favorable clinical outcomes (five-year OS: 21% versus 10%, P<0.0001; five-year PFS: 10% versus 8%, P=0.014), but may not derive PFS benefit from the addition of chemotherapy to RT. The higher a patient’s EIR, the larger the potential benefit in the absence of chemotherapy. DVH parameters including heart mean dose and heart V10 were negatively associated with EIR. None of these DVH parameters was correlated with the clinical outcomes.

Conclusion

EIR may serve as a potential biomarker to predict OS and PFS in NSCLC patients treated with RT. These findings require prospective studies to evaluate the role of such prognostic marker to identify patients at risk to tailor interventions.

Severe eosinophilia and subsequent dermatologic immune‐related adverse event with squamous cell carcinoma antigen elevation induced by nivolumab and ipilimumab

Immune checkpoint inhibitors (ICIs) for malignant lesions are associated with immune‐related adverse events (irAEs), but reports about severe eosinophilia induced by ICIs are scarce. A 73‐year‐old man with lung squamous cell carcinoma was treated by chemotherapy (carboplatin plus paclitaxel) and ICIs (nivolumab plus ipilimumab). After two cycles of chemotherapy, the ICIs were continued. After 5 months, the eosinophilia, which had exceeded 5000/μl, increasingly deteriorated, and the only detected irAE was a grade 1 rash. Under continuation of the ICIs, although the eosinophilia decreased, a grade 3 rash and severe pruritis subsequently appeared. Squamous cell carcinoma antigen (SCCA) was steeply increased simultaneously. A complete response had been achieved, and oral prednisolone markedly improved the rash, pruritis, and eosinophilia. Clinicians should be aware that precedent severe eosinophilia and subsequent severe irAE could occur in patients treated by nivolumab and ipilimumab, and SCCA elevation could be associated with dermatologic irAE.

Blood Eosinophils Are Associated with Efficacy of Targeted Therapy in Patients with Advanced Melanoma

Background: Eosinophils appear to contribute to the efficacy of immunotherapy and their frequency was suggested as a predictive biomarker. Whether this observation could be transferred to patients treated with targeted therapy remains unknown. Methods: Blood and serum samples of healthy controls and 216 patients with advanced melanoma were prospectively and retrospectively collected. Freshly isolated eosinophils were phenotypically characterized by flow cytometry and co-cultured in vitro with melanoma cells to assess cytotoxicity. Soluble serum markers and peripheral blood counts were used for correlative studies. Results: Eosinophil-mediated cytotoxicity towards melanoma cells, as well as phenotypic characteristics, were similar when comparing healthy donors and patients. However, high relative pre-treatment eosinophil counts were significantly associated with response to MAPKi (p = 0.013). Eosinophil-mediated cytotoxicity towards melanoma cells is dose-dependent and requires proximity of eosinophils and their target in vitro. Treatment with targeted therapy in the presence of eosinophils results in an additive tumoricidal effect. Additionally, melanoma cells affected eosinophil phenotype upon co-culture. Conclusion: High pre-treatment eosinophil counts in advanced melanoma patients were associated with a significantly improved response to MAPKi. Functionally, eosinophils show potent cytotoxicity towards melanoma cells, which can be reinforced by MAPKi. Further studies are needed to unravel the molecular mechanisms of our observations.

The Hodgkin Lymphoma Immune Microenvironment: Turning Bad News into Good

The classic Hodgkin lymphoma (cHL) tumor microenvironment (TME) is by far the most abundant component of tumors and is responsible for most of their biological and clinical characteristics. Recent advances in our knowledge of these networks in cellular interactions allow us to understand that the neoplastic Hodgkin and Reed Sternberg (HRS) cells, although they are in the minority, are the main architects of this dysregulated immune milieu. Here, we review the major changes that have happened in recent years: from TME as a helpless bystander, reflecting an ineffective immune response, to a dynamic tumor-promoting and immunosuppressive element. The HRS cells promote survival through interconnected intrinsic and extrinsic alterations, boosting pro-tumoral signaling pathways through genetic aberrations and autocrine growth signals, in parallel with abnormal cytokine secretion for the recruitment and selection of the best cell partners for this immunosuppressive TME. In turn, cHL is already proving to be the perfect model with which to address an immune checkpoint blockade. Preliminary data demonstrate the utility of druggable key signaling pathways in this ensemble, such as JAK-STAT, NF-κB, and others. In addition, myriad biomarkers predicting a response await validation by new in situ multiplex analytical methods, single-cell gene expression, and other techniques. Together, these components will define the functional phenotypes with which we will elucidate the molecular pathogenesis of the disease and improve the survival of patients who are refractory to conventional therapies.

Eosinophils and melanoma: Implications for immunotherapy

New therapies such as immune checkpoint blockers (ICB) have offered extended survival to patients affected by advanced melanoma. However, ICBs have demonstrated debilitating side effects on the joints, liver, lungs, skin, and gut. Several biomarkers have been identified for their role in predicting which patients better tolerate ICBs. Still, these biomarkers are limited by immunologic and genetic heterogeneity and the complexity of translation into clinical practice. Recent observational studies have suggested eosinophil counts, and serum levels of eosinophil cationic protein are significantly associated with prolonged survival in advanced-stage melanoma. It is likely that eosinophils thereby modulate treatment response through mechanisms yet to be explored. Here, we review the functionality of eosinophils, their oncogenic role in melanoma and discuss how these mechanisms may influence patient response to ICBs and their implications in clinical practice.

Stemness, Inflammation and Epithelial-Mesenchymal Transition in Colorectal Carcinoma: The Intricate Network

In global cancer statistics, colorectal carcinoma (CRC) ranks third by incidence and second by mortality, causing 10.0% of new cancer cases and 9.4% of oncological deaths worldwide. Despite the development of screening programs and preventive measures, there are still high numbers of advanced cases. Multiple problems compromise the treatment of metastatic colorectal cancer, one of these being cancer stem cells—a minor fraction of pluripotent, self-renewing malignant cells capable of maintaining steady, low proliferation and exhibiting an intriguing arsenal of treatment resistance mechanisms. Currently, there is an increasing body of evidence for intricate associations between inflammation, epithelial–mesenchymal transition and cancer stem cells. In this review, we focus on inflammation and its role in CRC stemness development through epithelial–mesenchymal transition.

A CIBERSORTx-based immune cell scoring system could independently predict the prognosis of patients with myelodysplastic syndromes

Aside from cell intrinsic factors such as genetic alterations, immune dysregulation in the bone marrow (BM) microenvironment plays a role in the development and progression of myelodysplastic syndromes (MDS). However, the prognostic implications of various immune cells in patients with MDS remain unclear. We adopted CIBERSORTx to estimate the relative fractions of 22 subtypes of immune cells in the BM of 316 patients with MDS and correlated the results with clinical outcomes. A lower fraction of unpolarized M0 macrophages and higher fractions of M2 macrophages and eosinophils were significantly associated with inferior survival. An immune cell scoring system (ICSS) was constructed based on the proportion of these 3 immune cells in the BM. The ICSS high-risk patients had higher BM blast counts, higher frequencies of poor-risk cytogenetics, and more NPM1, TP53, and WT1 mutations than intermediate- and low-risk patients. The ICSS could stratify patients with MDS into 3 risk groups with distinct leukemia-free survival and overall survival among the total cohort and in the subgroups of patients with lower and higher disease risk based on the revised International Prognostic Scoring System (IPSS-R). The prognostic significance of ICSS was also validated in another independent cohort. Multivariable analysis revealed that ICSS independently predicted prognosis, regardless of age, IPSS-R, and mutation status. Bioinformatic analysis demonstrated a significant correlation between high-risk ICSS and nuclear factor κB signaling, oxidative stress, and leukemic stem cell signature pathways. Further studies investigating the mechanistic insight into the crosstalk between stem cells and immune cells are warranted.

The Role of Innate Immune Cells in Tumor Invasion and Metastasis

Simple Summary

Tumor invasion and metastasis are one of the main reasons patients succumb to cancer. In this review, we summarize recent studies which provide evidence on the involvement of cells of the innate immune system and their function in invasion and metastasis.

Abstract

Metastasis is considered one of the hallmarks of cancer and enhanced tumor invasion and metastasis is significantly associated with cancer mortality. Metastasis occurs via a series of integrated processes involving tumor cells and the tumor microenvironment. The innate immune components of the microenvironment have been shown to engage with tumor cells and not only regulate their proliferation and survival, but also modulate the surrounding environment to enable cancer progression. In the era of immune therapies, it is critical to understand how different innate immune cell populations are involved in this process. This review summarizes recent literature describing the roles of innate immune cells during the tumor metastatic cascade.

CCL24 Signaling in the Tumor Microenvironment

Chemokines with their network play an important role in cancer growth, metastasis, and host-tumor interactions. Of many chemokines, C-C motif chemokine ligand 24 (CCL24) has been shown to contribute to tumorigenesis as well as inflammatory diseases like asthma, allergies, and eosinophilic esophagitis. CCL24 is expressed in some tumor cells such as colon cancer, hepatocellular carcinoma, and cutaneous T cell lymphoma. CCL24 can be used as a potential biomarker in several cancers including colon cancer, non-small cell cancer, and nasopharyngeal carcinoma as the plasma level of CCL24 is increased. The various functions of CCL24 contribute to the biology of cancer by M2 macrophage polarization, angiogenesis, invasion and migration, and recruitment of eosinophils.

Inflammation and tumor progression: signaling pathways and targeted intervention

Cancer development and its response to therapy are regulated by inflammation, which either promotes or suppresses tumor progression, potentially displaying opposing effects on therapeutic outcomes. Chronic inflammation facilitates tumor progression and treatment resistance, whereas induction of acute inflammatory reactions often stimulates the maturation of dendritic cells (DCs) and antigen presentation, leading to anti-tumor immune responses. In addition, multiple signaling pathways, such as nuclear factor kappa B (NF-kB), Janus kinase/signal transducers and activators of transcription (JAK-STAT), toll-like receptor (TLR) pathways, cGAS/STING, and mitogen-activated protein kinase (MAPK); inflammatory factors, including cytokines (e.g., interleukin (IL), interferon (IFN), and tumor necrosis factor (TNF)-α), chemokines (e.g., C-C motif chemokine ligands (CCLs) and C-X-C motif chemokine ligands (CXCLs)), growth factors (e.g., vascular endothelial growth factor (VEGF), transforming growth factor (TGF)-β), and inflammasome; as well as inflammatory metabolites including prostaglandins, leukotrienes, thromboxane, and specialized proresolving mediators (SPM), have been identified as pivotal regulators of the initiation and resolution of inflammation. Nowadays, local irradiation, recombinant cytokines, neutralizing antibodies, small-molecule inhibitors, DC vaccines, oncolytic viruses, TLR agonists, and SPM have been developed to specifically modulate inflammation in cancer therapy, with some of these factors already undergoing clinical trials. Herein, we discuss the initiation and resolution of inflammation, the crosstalk between tumor development and inflammatory processes. We also highlight potential targets for harnessing inflammation in the treatment of cancer.

Eosinophilic pleural effusion due to lung cancer has a better prognosis than non-eosinophilic malignant pleural effusion

Objective

Tumor-related eosinophilia may have extended survival benefits for some cancer patients. However, there has been no report on the prognosis difference between eosinophilic pleural effusion (EPE) and non-EPE in lung cancer patients. Our study aimed to investigate the prognosis difference between EPE and non-EPE due to lung cancer.

Patients and methods

We retrospectively reviewed patients diagnosed with lung cancer who presented with malignant pleural effusion (MPE) between May 2007 and September 2020 at the National Hospital Organization Kochi Hospital. EPE is defined as pleural fluid with a nucleated cell count containing 10% or more eosinophils.

Results

A total of 152 patients were included: 89 were male (59%). The median age was 74.4 years (range 37–101), and all patients were pathologically shown to have MPE. Most patients (140; 92%) had an Eastern Cooperative Oncology Group (ECOG) Performance Status (PS) of 0/1. Twenty patients had EPE. The median overall survival (OS) of all 152 lung cancer patients with MPE was 298 days. The median OS of the patients with EPE was 766 days, and the median OS of the patients with non-EPE was 252 days. Kaplan–Meier univariate analysis showed that lung cancer patients with EPE had a significantly better prognosis than patients with non-EPE (P < 0.05). Cox proportional regression analysis showed that EPE, ECOG PS, sex, and the neutrophil-to-lymphocyte ratio in the serum (sNLR) may be independent prognostic factors affecting survival in patients with MPE.

Conclusion

Lung cancer patients with EPE have a better prognosis than those with non-EPE.

Eosinophils in skin diseases

Eosinophil infiltration is a common finding in a broad spectrum of skin diseases, despite the fact that the skin is devoid of eosinophils under physiologic conditions. Although cutaneous eosinophilia is reactive, cytokine-mediated in most cases, diseases with an intrinsic mutation-mediated clonal expansion of eosinophils can also manifest on the skin. As eosinophils are involved in host defense, regulate immune responses, generate pruritus, induce remodeling and fibrosis, and can cause tissue damage, they have the capacity to actively contribute to the pathogenesis of diseases. Recent research provided deeper insights in the mechanisms, e.g., bacterial and viral clearance, blister formation, recruitment of cytotoxic T cells, and generation of pruritus, by which eosinophils might come into action. This review aims at providing an overview on the clinical presentations of eosinophil-associated dermatoses and the current understanding of their pathogenic role in these diseases. Further, we discuss the effects of therapies targeting eosinophils.

Engaging the Innate and Adaptive Antitumor Immune Response in Lymphoma

Immunotherapy has emerged as a powerful therapeutic strategy for many malignancies, including lymphoma. As in solid tumors, early clinical trials have revealed that immunotherapy is not equally efficacious across all lymphoma subtypes. For example, immune checkpoint inhibition has a higher overall response rate and leads to more durable outcomes in Hodgkin lymphomas compared to non-Hodgkin lymphomas. These observations, combined with a growing understanding of tumor biology, have implicated the tumor microenvironment as a major determinant of treatment response and prognosis. Interactions between lymphoma cells and their microenvironment facilitate several mechanisms that impair the antitumor immune response, including loss of major histocompatibility complexes, expression of immunosuppressive ligands, secretion of immunosuppressive cytokines, and the recruitment, expansion, and skewing of suppressive cell populations. Accordingly, treatments to overcome these barriers are being rapidly developed and translated into clinical trials. This review will discuss the mechanisms of immune evasion, current avenues for optimizing the antitumor immune response, clinical successes and failures of lymphoma immunotherapy, and outstanding hurdles that remain to be addressed.

Reactive Eosinophil Proliferations in Tissue and the Lymphocytic Variant of Hypereosinophilic Syndrome

OBJECTIVES

The 2019 Society for Hematopathology and European Association for Haematopathology Workshop reviewed the spectrum of neoplastic, nonneoplastic, and borderline entities associated with reactive eosinophilia in tissue.

METHODS

The workshop panel reviewed 46 cases covered in 2 workshop sessions.

RESULTS

The 46 cases were presented with their consensus diagnoses during the workshop. Reactive eosinophilia in lymph nodes and other tissues may be accompanied by or be distinct from peripheral blood eosinophilia. Reactive etiologies included inflammatory disorders such as Kimura disease and IgG4-related disease, which may show overlapping pathologic features and reactions to infectious agents and hypersensitivity (covered in a separate review). Hodgkin, T-cell, and B-cell lymphomas and histiocytic neoplasms can result in reactive eosinophilia. The spectrum of these diseases is discussed and illustrated through representative cases.

CONCLUSIONS

Reactive eosinophilia in lymph nodes and tissues may be related to both nonneoplastic and neoplastic lymphoid proliferations and histiocytic and nonhematolymphoid processes. Understanding the differential diagnosis of reactive eosinophilia and the potential for overlapping clinical and pathologic findings is critical in reaching the correct diagnosis so that patients can be treated appropriately.

Eosinophils in the Tumor Microenvironment

Eosinophils are rare blood-circulating and tissue-infiltrating immune cells studied for decades in the context of allergic diseases and parasitic infections. Eosinophils can secrete a wide array of soluble mediators and effector molecules, with potential immunoregulatory activities in the tumor microenvironment (TME). These findings imply that these cells may play a role in cancer immunity. Despite these cells were known to infiltrate tumors since many years ago, their role in TME is gaining attention only recently. In this chapter, we will review the main biological functions of eosinophils that can be relevant within the TME. We will discuss how these cells may undergo phenotypic changes acquiring pro- or antitumoricidal properties according to the surrounding stimuli. Moreover, we will analyze canonical (i.e., degranulation) and unconventional mechanisms (i.e., DNA traps, exosome secretion) employed by eosinophils in inflammatory contexts, which can be relevant for tumor immune responses. Finally, we will review the available preclinical models that could be employed for the study of the role in vivo of eosinophils in cancer.

Primary tumors from mucosal barrier organs drive unique eosinophil infiltration patterns and clinical associations

Eosinophils are bone marrow-derived granulocytes that display key effector functions in allergic diseases. Nonetheless, recent data highlight important roles for eosinophils in the tumor microenvironment (TME). Eosinophils have been attributed with pleiotropic and perhaps conflicting functions, which may be attributed at least in part to variations in eosinophil quantitation in the TME. Thus, a reliable, quantitative, and robust method for the assessment of eosinophilic infiltration in the TME is required. This type of methodology could standardize the identification of these cells and promote the subsequent generation of hypothesis-driven mechanistic studies. To this end, we conducted a comprehensive analysis of multiple primary tumors from distinct anatomical sites using a standardized method. Bioinformatics analysis of 10,469 genomically profiled primary tumors revealed that eosinophil abundance within different tumors can be categorized into three groups representing tumors with high, intermediate, and low eosinophil levels. Consequently, eosinophil abundance, as well as spatial distribution, was determined in tissue tumor arrays of six tumors representing all three classifications (colon and esophagus - high; lung - intermediate; cervix, ovary, and breast - low). With the exception of breast cancer, eosinophils were mainly localized in the tumor stroma. Importantly, the tumor anatomical site was identified as the primary predictive factor of eosinophil stromal density highlighting a distinction between mucosal-barrier organs versus non-mucosal barrier organs. These findings enhance our understanding of eosinophil diversity in the TME and provide a compelling rationale for future experiments assessing the activity of these cells.

A new dawn for eosinophils in the tumour microenvironment

Eosinophils are evolutionarily conserved, pleotropic cells that display key effector functions in allergic diseases, such as asthma. Nonetheless, eosinophils infiltrate multiple tumours and are equipped to regulate tumour progression either directly by interacting with tumour cells or indirectly by shaping the tumour microenvironment (TME). Eosinophils can readily respond to diverse stimuli and are capable of synthesizing and secreting a large range of molecules, including unique granule proteins that can potentially kill tumour cells. Alternatively, they can secrete pro-angiogenic and matrix-remodelling soluble mediators that could promote tumour growth. Herein, we aim to comprehensively outline basic eosinophil biology that is directly related to their activity in the TME. We discuss the mechanisms of eosinophil homing to the TME and examine their diverse pro-tumorigenic and antitumorigenic functions. Finally, we present emerging data regarding eosinophils as predictive biomarkers and effector cells in immunotherapy, especially in response to immune checkpoint blockade therapy, and highlight outstanding questions for future basic and clinical cancer research.

The Emerging Role of Eosinophils as Multifunctional Leukocytes in Health and Disease

Eosinophils are terminally differentiated cytotoxic effector cells that have a role in parasitic infections and allergy by releasing their granule-derived cytotoxic proteins. However, an increasing number of recent observations indicate that eosinophils are not only associated with the pathogenesis of a wide range of diseases, but also contribute to the maintenance of homeostatic responses in previously underappreciated diverse tissues, such as the gastrointestinal (GI) tract and adipose tissue. In this review, we describe biological characteristics of eosinophils, as their developmental properties, permissive proliferation and survival, degranulation activity, and migration properties enable them to distribute to both homeostatic and inflamed tissues. We describe pathologic aspects of eosinophils with a role in asthma and in various GI diseases, including eosinophilic GI disorders, inflammatory bowel disease, and radiation-induced enteropathy. Finally, we discuss the beneficial role of eosinophils, which contribute to the resolution of pathogenic conditions and to the modulation of homeostatic biologic responses.

Identification of a novel IL-5 signaling pathway in chronic pancreatitis and crosstalk with pancreatic tumor cells

BACKGROUND

While inflammation is associated with pancreatic cancer, the underlying mechanisms leading to cancer initiation are still being delineated. Eosinophils may promote or inhibit tumor growth, although the specific role in pancreatic cancer has yet to be determined. Eosinophil-supporting cytokine interleukin-5 and receptor are likely to have a role, but the significance in the pancreatic cancer microenvironment is unknown.

METHODS

Genetically engineered Akt1^Myr/KRas^G12D and KRas^G12D mice were used to model changes induced by chronic inflammation. Tissue samples were collected to analyze the tumor microenvironment and infiltration of immune cells, whereas serum was collected to analyze cytokine and amylase activity in the inflammatory model. The expression of IL-5R and the effects of IL-5 were analyzed in human and murine tumor cells.

RESULTS

Compound Akt1^Myr/KRas^G12D mice, compared to single KRas^G12D or Akt1^Myr mice, exhibited increased tissue damage after repeat inductions of inflammation, and had accelerated tumor development and metastasis. M2 macrophages and newly identified eosinophils co-localized with fibrotic regions rather than infiltrating into tumors, consistent with immune cell privilege. The majority of eosinophils found in the pancreas of Akt1^Myr/KRas^G12D mice with chronic inflammation lacked the cytotoxic NKG2D marker. IL-5 expression was upregulated in pancreatic cells in response to inflammation, and then diminished in advanced lesions. Although not previously described in pancreatic tumors, IL-5Rα was increased during mouse pancreatic tumor progression and expressed in human pancreatic ductal adenocarcinomas (7 of 7 by immunohistochemistry). IL-5 stimulated tumor cell migration and activation through STAT5 signaling, thereby suggesting an unreported tumor-promoting role for IL-5Rα in pancreatic cancer.

CONCLUSIONS

Chronic inflammation induces increased pancreatic cancer progression and immune cells such as eosinophils are attracted to areas of fibrosis. Results suggest that IL-5 in the pancreatic compartment stimulates increased IL-5Rα on ductal tumor cells to increase pancreatic tumor motility. Collectively, IL-5/IL-5Rα signaling in the mouse and human pancreatic tumors microenvironment is a novel mechanism to facilitate tumor progression. Additional file 1: Video Abstract.

Immunocheckpoint Inhibitor- (Nivolumab-) Associated Hypereosinophilia in Non-Small-Cell Lung Carcinoma

Immunocheckpoint inhibitor (ICI) therapy has provided significant clinical improvements in the treatment of several malignancies. The purpose of this report is to increase awareness of hypereosinophilia associated with checkpoint inhibitors, a topic that has been rarely reported. Hypereosinophilia may need to be addressed especially if eosinophil counts increase to levels where hypereosinophilic visceral complications can occur. We are presenting a case of a 57-year-old male with hypereosinophilia that was seen in the setting of progression of metastatic non-small-cell lung cancer during and after nivolumab treatment.

Tumor-associated tissue eosinophilia predicts favorable clinical outcome in solid tumors: a meta-analysis

Background

Activated eosinophils have been deemed to affect carcinogenesis and tumor progression via various mechanisms in tumor microenvironment. However, the prognostic role of tumor-associated tissue eosinophilia (TATE) in human cancers remains controversial. Therefore, we conducted this meta-analysis to better comprehend the association between TATE and clinical outcomes of patients.

Methods

We searched PubMed, Embase and EBSCO to determine the researches assessing the association between TATE and overall survival (OS) and/or disease-free survival (DFS) in patients with cancer, then combined relevant data into hazard ratios (HRs) or odds ratio (OR) for OS, DFS and clinicopathological features including lymph node metastasis etc. with STATA 12.0.

Results

Twenty six researches with 6384 patients were included in this meta-analysis. We found that the presence of TATE was significantly associated with improved OS, but not with DFS in all types of cancers. In stratified analyses based on cancer types, pooled results manifested that the infiltration of eosinophils was remarkably associated with better OS in esophageal carcinoma and colorectal cancer. In addition, TATE significantly inversely correlated with lymph node metastasis, tumor stage and lymphatic invasion of cancer.

Conclusion

TATE promotes survival in cancer patients, suggesting that it is a valuable prognostic biomarker and clinical application of biological response modifiers or agonists promoting TATE may be the novel therapeutic strategy for patients.

Regulation of Tumor Immunity by Lysophosphatidic Acid

The tumor microenvironment (TME) may be best conceptualized as an ecosystem comprised of cancer cells interacting with a multitude of stromal components such as the extracellular matrix (ECM), blood and lymphatic networks, fibroblasts, adipocytes, and cells of the immune system. At the center of this crosstalk between cancer cells and their TME is the bioactive lipid lysophosphatidic acid (LPA). High levels of LPA and the enzyme generating it, termed autotaxin (ATX), are present in many cancers. It is also well documented that LPA drives tumor progression by promoting angiogenesis, proliferation, survival, invasion and metastasis. One of the hallmarks of cancer is the ability to modulate and escape immune detection and eradication. Despite the profound role of LPA in regulating immune functions and inflammation, its role in the context of tumor immunity has not received much attention until recently where emerging studies highlight that this signaling axis may be a means that cancer cells adopt to evade immune detection and eradication. The present review aims to look at the immunomodulatory actions of LPA in baseline immunity to provide a broad understanding of the subject with a special emphasis on LPA and cancer immunity, highlighting the latest progress in this area of research.

Hypereosinophilia in a patient with metastatic non-small-cell lung cancer treated with antiprogrammed cell death 1 (anti-PD-1) therapy

Immune checkpoint inhibitors have changed the treatment paradigm for patients with cancer. Though a majority of patients tolerate treatment, some develop hematologic toxicities, including eosinophilia. Eosinophilia has been associated with better responses in some patients with melanoma, but this has not been investigated in non-small-cell lung cancer. We present a case of a woman with metastatic lung adenocarcinoma who developed asymptomatic hypereosinophilia after initiation of nivolumab. Her eosinophil count temporarily decreased after transiently stopping the medication, but increased again after re-initiation. She had a favorable tumor response to therapy. This exemplifies the potential role of eosinophilia as a peripheral, readily available biomarker of favorable response to immunotherapy in patients with lung cancer. Awareness of this manifestation is important.

Immune and Inflammatory Cells of the Tumor Microenvironment Represent Novel Therapeutic Targets in Classical Hodgkin Lymphoma

Classical Hodgkin Lymphoma (cHL) is a B-cell malignancy that, typically, responds well to standard therapies. However, patients who relapse after standard regimens or are refractory to induction therapy have a dismal outcome. The implementation of novel therapies such as the anti-CD30 monoclonal antibody Brentuximab Vedotin and immune checkpoint inhibitors has provided curative options for many of these patients. Nonetheless, responses are rarely durable, emphasizing the need for new agents. cHL is characterized by a unique microenvironment in which cellular and humoral components interact to promote tumor survival and dissemination. Knowledge of the complex composition of cHL microenvironment is constantly evolving; in particular, there is growing interest in certain cell subsets such as tumor-associated macrophages, myeloid-derived suppressor cells and neutrophils, all of which have a relevant role in the pathogenesis of the disease. The unique biology of the cHL microenvironment has provided opportunities to develop new drugs, many of which are currently being tested in preclinical and clinical settings. In this review, we will summarize novel insights in the crosstalk between tumor cells and non-malignant inflammatory cells. In addition, we will discuss the relevance of tumor-microenvironment interactions as potential therapeutic targets.

Cell of Origin and Immunologic Events in the Pathogenesis of Breast Implant-Associated Anaplastic Large-Cell Lymphoma

Breast implant–associated anaplastic large-cell lymphoma (BIA-ALCL) is a CD30-positive, anaplastic lymphoma kinase–negative T-cell lymphoma. Nearly all cases have been associated with textured implants. Most cases are of effusion-limited, indolent disease, with an excellent prognosis after implant and capsule removal. However, capsular invasion and tumor mass have a more aggressive course and a fatal outcome risk. This review summarizes the current knowledge on BIA-ALCL cell of origin and immunologic factors underlying its pathogenesis. Cytokine expression profiling of BIA-ALCL cell lines and clinical specimens reveals a predominantly type 17 helper T-cell (Th17)/Th1 signature, implicating this as its cell of origin. However, a Th2 allergic inflammatory response is suggested by the presence of IL-13, with infiltration of eosinophils and IgE-coated mast cells in clinical specimens of BIA-ALCL. The microenvironment-induced T-cell plasticity, a factor increasingly appreciated, may partially explain these divergent results. Mutations resulting in constitutive Janus kinase (JAK)–STAT activation have been detected and associated with BIA-ALCL pathogenesis in a small number of cases. One possible scenario is that an inflammatory microenvironment stimulates an immune response, followed by polyclonal expansion of Th17/Th1 cell subsets with release of inflammatory cytokines and chemokines and accumulation of seroma. JAK-STAT3 gain-of-function mutations within this pathway and others may subsequently lead to monoclonal T-cell proliferation and clinical BIA-ALCL. Current research suggests that therapies targeting JAK proteins warrant investigation in BIA-ALCL.

Prognostic values of lymphocyte and eosinophil counts in resectable cervical squamous cell carcinoma

Aim: Cervical cancer is one of the leading causes of cancer mortality in women. Peripheral white blood cell parameters such as neutrophil (NE), eosinophil (EO), basophil (BA), as well as lymphocyte (LY) and monocyte (MO), are correlated with tumor outcomes. Methods: In total, 110 cervical squamous cell carcinoma patients were recruited in this study. The potential prognostic factors were evaluated by univariate and multivariate survival analysis. Results: Cox regression analysis model indicated that higher pretreatment EO level and increased post-/preradiotherapy EO ratio were independently associated with worse progression-free survival. Lower pretreatment LY or higher EO levels and increased post-/preradiotherapy EO ratio were independently associated with worse overall survival. Conclusion: LY and EO are correlated with outcomes of cervical squamous cell cancer.

Eosinophil-cationic protein - a novel liquid prognostic biomarker in melanoma

BACKGROUND

The role of eosinophils in cancer is not yet completely understood, but patients with eosinophilia show a trend towards longer survival in several types of cancer, including melanoma. However, eosinophil count at initial diagnosis of metastatic melanoma does not predict survival. Since eosinophil cationic protein (ECP) mediates anticancer effects, such as tissue remodelling and cytotoxic activity, we investigated this marker as an early prognostic marker in metastatic melanoma.

METHODS

Serum of 56 melanoma patients was collected at the time of diagnosis of metastatic disease. ECP levels as measured by ELISA were correlated with overall survival (OS) in patients before systemic therapy with immunotherapy or chemotherapy. Statistical analyses were performed using the Log-Rank (Mantel-Cox) test.

RESULTS

The median OS for patients with high serum ECP above 12.2 ng/ml was 12 months (n = 39), compared to 28 months for patients with ECP below this threshold (n = 17; p = 0.0642). In patients with cutaneous melanoma, excluding patients with uveal and mucosal melanoma, the survival difference was even more striking (p = 0.0393). ECP's effect size on OS was observed independently of the consecutive therapy. ECP levels were not correlated with LDH levels.

CONCLUSION

ECP seems to be a novel prognostic serum marker for the outcome of melanoma patients, which is independent of LDH and easy to perform in clinical practice. The striking negative prognostic value of high ECP level is unanticipated and can guide patient management.

Values of applying white blood cell counts in the prognostic evaluation of resectable colorectal cancer

The count and classification of white blood cells (WBCs) may be used as prognostic markers in certain types of cancer. The present study investigated the prognostic potential of the counts of WBCs, including lymphocytes (LYs), monocytes (MOs), neutrophils (NEs), eosinophils (EOs) and basophils (BAs), in the prognosis of resectable colorectal cancer. The present study recruited 153 resectable colorectal cancer cases retrospectively, which were pathologically confirmed. All patients were divided into two groups, according to the median value of LY (low LY, ≤1.632x109/l or high LY, >1.632x109/l), MO (low MO, ≤0.330x109/l or high MO, >0.330x109/l), NE (low NE, ≤3.600x109/l or high NE, >3.600x109/l), EO (low EO, ≤0.085x109/l or high EO, >0.085x109/l), BA (low BA, ≤0.010x109/l or high BA, >0.010x109/l), or WBC (low WBC, ≤5.780x109/l or high WBC, >5.780x109/l). To evaluate the alterations in WBC counts following surgery and adjuvant chemotherapy; all samples received oxiplatin and capecitabine (XELOX) for 6‑8 cycles or 5‑fluorouracil, leucovorin and oxaliplatin (mFOLFOX6) for 10‑12 cycles. XELOX included oxaliplatin administered intravenously at a dose of 130 mg/m2 on day 1 and 850‑1,250 mg/m2 capecitabine twice daily for days 1‑14, repeated every 3 weeks. mFOLFOX6 included oxaliplatin administered intravenously at a dose of 85 mg/m2, 400 mg/m2 leucovorin and 400 mg/m2 5‑FU on day 1 followed by 1,200 mg/m2/days continuous infusion for 2 days (in total, 2,400 mg/m2 over 46‑48 h), repeated every 2 weeks. The present study investigated the post/pre‑treatment of LY, MO, NE, EO, BA and WBC ratios (≤1 indicated that LY, MO, NE, EO, BA and WBC counts were not increased following therapy; whereas, >1 suggested increased counts). Kaplan‑Meier curves were constructed to demonstrate overall survival (OS). A multivariate and univariate logistic regression analyses model was employed to identify the independent risk factors. Low pre‑treatment BA counts were associated with larger tumor size (>5 cm); pre‑treatment BA levels were positively associated with OS. Surgery significantly decreased the count of BAs and increased the count of EOs; whereas, no effect was observed on LYs, MOs, NEs or WBCs. Adjuvant chemotherapy markedly decreased the counts of LY, NE and WBC; whereas, no notable effects on MOs, EOs or BAs were observed. Whole course treatment (surgery combined with adjuvant chemotherapy) significantly decreased the values of LY, NE and WBC; however, increased the value of EO; no effects on the MO or BA counts were observed. An increased post‑/pre‑treatment NE ratio suggested poorer prognosis. Multivariate Cox regression analysis revealed that sex, tumor size, pre‑treatment BA count and the post‑/pre‑treatment NE ratio were independent prognostic factors affecting OS. The results of the present study suggested that the pre‑treatment BA count and post‑/pre‑treatment NE ratio may be potential prognostic factors for resectable colorectal cancer.

High tumour plasma cell infiltration reflects an important microenvironmental component in classic Hodgkin lymphoma linked to presence of B-symptoms

Plasma cells are important prognostic actors in different malignancies. The tumour microenvironmental composition in classic Hodgkin lymphoma (cHL) is a major prognostic key element; however, clinicopathological studies regarding plasma cells in cHL are lacking. The aim of this study was to investigate CD138+ (also termed SDC1+) plasma cell and IgG4 producing (IgG4+) plasma cells infiltration in the microenvironment of cHL. Immunohistochemistry with anti-CD138 and IgG4 antibodies was performed on diagnostic tumour biopsies from 124 patients with cHL, on tissue micro array (TMA). In 120 cases, CD138+ plasma cell-infiltration was associated with the presence of B-symptoms (P = 0·028) and advanced stage, IIB-IVB (P = 0·009). In multivariate analysis, CD138+ plasma cells correlated with eosinophil infiltration (P = 0·013). The subgroup of IgG4+ plasma cells was analysed in 122 cases and only correlated to CD138+ plasma cells (P = 0·004). Patients with high proportion of tumour infiltrating CD138+ plasma cells (defined as ≥10%), had a more inferior event-free survival (P = 0·007) and overall survival (P = 0·004) than patients with a low proportion of infiltrating CD138+ plasma cells (<10%), although significance was not maintained in multivariate analysis. In summary, a high proportion of tumour-associated plasma cells in cHL reflect an important component in the microenvironment of cHL.

Potential impact of invasive surgical procedures on primary tumor growth and metastasis

Surgical procedures such as tumor resection and biopsy are still the gold standard for diagnosis and (determination of) treatment of solid tumors, and are prognostically beneficial for patients. However, growing evidence suggests that even a minor surgical trauma can influence several (patho) physiological processes that might promote postoperative metastatic spread and tumor recurrence. Local effects include tumor seeding and a wound healing response that can promote tumor cell migration, proliferation, differentiation, extracellular matrix remodeling, angiogenesis and extravasation. In addition, local and systemic immunosuppression impairs antitumor immunity and contributes to tumor cell survival. Surgical manipulation of the tumor can result in cancer cell release into the circulation, thus increasing the chance of tumor cell dissemination. To prevent these undesired effects of surgical interventions, therapeutic strategies targeting immune response exacerbation or alteration have been proposed. This review summarizes the current literature regarding these local, systemic and secondary site effects of surgical interventions on tumor progression and dissemination, and discusses studies that aimed to identify potential therapeutic approaches to prevent these effects in order to further increase the clinical benefit from surgical procedures.

The Microenvironment in Epstein-Barr Virus-Associated Malignancies

The Epstein–Barr virus (EBV) can cause a wide variety of cancers upon infection of different cell types and induces a highly variable composition of the tumor microenvironment (TME). This TME consists of both innate and adaptive immune cells and is not merely an aspecific reaction to the tumor cells. In fact, latent EBV-infected tumor cells utilize several specific mechanisms to form and shape the TME to their own benefit. These mechanisms have been studied largely in the context of EBV+ Hodgkin lymphoma, undifferentiated nasopharyngeal carcinoma, and EBV+ gastric cancer. This review describes the composition, immune escape mechanisms, and tumor cell promoting properties of the TME in these three malignancies. Mechanisms of susceptibility which regularly involve genes related to immune system function are also discussed, as only a small proportion of EBV-infected individuals develops an EBV-associated malignancy.

An anergic immune signature in the tumor microenvironment of classical Hodgkin lymphoma is associated with inferior outcome

OBJECTIVE

The classical Hodgkin lymphoma (cHL) tumor microenvironment shows an ongoing inflammatory response consisting of varying degrees of infiltrating eosinophils, mast cells, macrophages, regulatory T lymphocytes (Tregs), and activated lymphocytes surrounding the malignant cells. Herein, different immune signatures are characterized and correlated with treatment outcome.

METHODS

Tumor-infiltrating leukocytes were phenotyped in biopsies from 459 patients with cHL. Time to progression (TTP) (primary progression, relapse, or death from cHL) and overall survival were analyzed using Cox proportional hazards regression.

RESULTS

The leukocyte infiltration in the microenvironment was highly diverse between patients and was categorized in 4 immune signatures (active, anergic, innate, or mixed). A high proportion of Tregs (anergic) resulted in shorter TTP (median 12.9-year follow-up) in age-adjusted analyses (hazard ratio = 1.82; 95% confidence interval 1.05-3-15). Epstein-Barr virus (EBV)-positive cases had higher proportions of macrophages and activated lymphocytes than EBV negative, but neither of those leukocytes predicted prognosis.

CONCLUSIONS

Abundant Tregs (anergic signature) indicate a shorter TTP, particularly in younger patients. This is probably due to a reduced ability of the immune system to attack the tumor cells. Our data warrant further investigation if these suggested immune signatures could predict outcome of immunotherapy such as immune checkpoint inhibitors.

Eosinophils: The unsung heroes in cancer?

Prolonged low-grade inflammation or smoldering inflammation is a hallmark of a cancer. Eosinophils are components of the immune microenvironment that modulates tumor initiation and progression. Although canonically associated with a detrimental role in allergic disorders, these cells can induce a protective immune response against helminthes, viral and bacterial pathogens. Eosinophils are a source of anti-tumorigenic (e.g., TNF-α, granzyme, cationic proteins, and IL-18) and protumorigenic molecules (e.g., pro-angiogenic factors) depending on the milieu. In several neoplasias (e.g., melanoma, gastric, colorectal, oral and prostate cancer) eosinophils play an anti-tumorigenic role, in others (e.g., Hodgkin's lymphoma, cervical carcinoma) have been linked to poor prognosis, whereas in yet others they are apparently innocent bystanders. These seemingly conflicting results suggest that the role of eosinophils and their mediators could be cancer-dependent. The microlocalization (e.g., peritumoral vs intratumoral) of eosinophils could be another important aspect in the initiation/progression of solid and hematological tumors. Increasing evidence in experimental models indicates that activation/recruitment of eosinophils could represent a new therapeutic strategy for certain tumors (e.g., melanoma). Many unanswered questions should be addressed before we understand whether eosinophils are an ally, adversary or neutral bystanders in different types of human cancers.

Bidirectional Mast Cell-Eosinophil Interactions in Inflammatory Disorders and Cancer

Human mast cells (MCs) and eosinophils were first described and named by Paul Ehrlich. These cells have distinct myeloid progenitors and differ morphologically, ultrastructurally, immunologically, biochemically, and pharmacologically. However, MCs and eosinophils play a pivotal role in several allergic disorders. In addition, these cells are involved in autoimmune disorders, cardiovascular diseases, and cancer. MCs are distributed throughout all normal human tissues, whereas eosinophils are present only in gastrointestinal tract, secondary lymphoid tissues, and adipose tissue, thymus, mammary gland, and uterus. However, in allergic disorders, MCs and eosinophils can form the "allergic effector unit." Moreover, in several tumors, MCs and eosinophils can be found in close proximity. Therefore, it is likely that MCs have the capacity to modulate eosinophil functions and vice versa. For example, interleukin 5, stem cell factor, histamine, platelet-activating factor (PAF), prostaglandin D2 (PGD2), cysteinyl leukotrienes, and vascular endothelial growth factors (VEGFs), produced by activated MCs, can modulate eosinophil functions through the engagement of specific receptors. In contrast, eosinophil cationic proteins such as eosinophil cationic protein and major basic protein (MBP), nerve growth factor, and VEGFs released by activated eosinophils can modulate MC functions. These bidirectional interactions between MCs and eosinophils might be relevant not only in allergic diseases but also in several inflammatory and neoplastic disorders.

Role of Eosinophil Granulocytes in Allergic Airway Inflammation Endotypes

Eosinophil granulocytes are intriguing members of the innate immunity system that have been considered important defenders during parasitic diseases as well as culprits during allergy-associated inflammatory diseases. Novel studies have, however, found new homoeostasis-maintaining roles for the cell. Recent clinical trials blocking different Th2 cytokines have uncovered that asthma is heterogeneous entity and forms different characteristic endotypes. Although eosinophils are present in allergic asthma with early onset, the cells may not be essential for the pathology. The cells are, however, likely disease causing in asthma with a late onset, which is often associated with chronic rhinosinusitis. Assessment of eosinophilia, fraction exhaled nitric oxide (FeNO) and periostin are markers that have emerged useful in assessing and monitoring asthma severity and endotype. Current scientific knowledge suggests that eosinophils are recruited by the inflammatory environment, activated by the innate interleukin (IL)-33 and prevented from apoptosis by both lymphocytes and innate immune cells such as type two innate immune cells. Eosinophils contain four specific granule proteins that exhibit an array of toxic and immune-modulatory activates. The granule proteins can be released by different mechanisms. Additionally, eosinophils contain a number of inflammatory cytokines and lipid mediators as well as radical oxygen species that might contribute to the disease both by the recruitment of other cells and the direct damage to supporting cells, leading to exacerbations and tissue fibrosis. This review aimed to outline current knowledge how eosinophils are recruited, activated and mediate damage to tissues and therapies used to control the cells.