Tumor associated macrophages and neutrophils in tumor progression

Different macrophages equally induce EMT in endometria of adenomyosis and normal

Endometrial cells and microenvironment are two important factors in the pathogenesis of adenomyosis. Our previous study demonstrated that macrophages can induce eutopic epithelial cells of adenomyosis to suffer from epithelial–mesenchymal transition (EMT). The aim of this study is to detect whether macrophages interacting with epithelial cells equally induce the EMT process in normal and eutopic endometria of healthy and adenomyotic patients; and whether macrophages parallelly polarize to M2. We investigated the expression levels of epithelial cadherin (E-cadherin), neural cadherin (N-cadherin), cytokeratin7 (CK7), vimentin, transforming growth factor-β1 (TGFB1), SMAD3 and pSMAD3 using immunohistochemistry and western blot, and then estimated the genetic levels of CD163, IL10 and MMP12 using real-time quantitative polymerase chain reaction (RT-PCR) in macrophages. Eutopic and normal endometrial tissues were obtained from 20 patients with adenomyosis and 11 control patients without adenomyosis, respectively. The immunohistochemical analysis shows distinct EMT in eutopic endometria in secretory phase; the expression levels of TGFB1, SMAD3 and pSMAD3 that indicate signal pathway of EMT were also higher in secretory phase. Macrophages can induce EMT process in primary endometrial epithelial cells derived from normal and eutopic endometria. After co-culturing, THP-1-derived macrophages polarized to M2. Compared with the eutopic endometrium group, further polarization to M2 was observed in the normal endometrium group. These results indicate that adenomyosis may be promoted by the pathologic EMT of epithelial cells, which is induced by macrophages that incapably polarize to M2.

Elevated pretreatment neutrophil/white blood cell ratio and monocyte/lymphocyte ratio predict poor survival in patients with curatively resected non-small cell lung cancer: Results from a large cohort

Background

The prognostic values of preoperative neutrophil/lymphocyte ratio (NLR), monocyte/lymphocyte ratio (MLR), and platelet/lymphocyte ratio (PLR) in non‐small cell lung cancer (NSCLC) have been previously described. This study assessed the prognostic values of other pretreatment complete blood cell parameters in Chinese patients with curatively resected NSCLC.

Methods

A total of 1466 consecutive NSCLC patients who received curative surgery from January 1, 2005 to December 31, 2009 with complete data from pretreatment blood tests were enrolled in this retrospective study. Correlations between each blood test parameter and overall survival were examined by Kaplan–Meier method or Cox proportional hazards regression, followed by a stratification analysis of significant variables.

Results

Optimal cut‐off values of 0.55 for neutrophil/white blood cell ratio (NWR), 0.28 for lymphocyte/white blood cell ratio (LWR), 0.09 for monocyte/white blood cell ratio (MWR), 2.06 for NLR, 0.35 for MLR, 204.00 for PLR, and 38.25 for platelet/white blood cell ratio (PWR) were identified using X‐tile software. Univariate analysis suggested that NWR ≥ 0.55, LWR < 0.28, MWR ≥ 0.09, NLR ≥ 2.06, MLR ≥ 0.35, and PLR ≥ 204.00 predicted a poor prognosis in NSCLC patients. However, only NWR and MLR were identified as independent significant prognostic factors in multivariable analysis, especially in tumor node metastasis stage I and I/II/III NSCLCs.

Conclusion

Pretreatment NWR, MWR, LWR, NLR, MLR, and PLR values are associated with poor overall survival for patients with curatively resected NSCLC. NWR and MLR are independent prognostic factors in curatively resected NSCLC.

Exploring the Potential of Nanotherapeutics in Targeting Tumor Microenvironment for Cancer Therapy

Advanced research in the field of cancer biology clearly demonstrated the key role of tumor microenvironment (TME) in cancer development and metastasis particularly in solid tumors. Components of TME, being non-neoplastic in nature provide supportive and permissive conditions for the growth of cancer cells. Hence it is important to modify TME in cancer therapy and this would be achieved by better understanding of TME morphological features and functioning of stromal components. Nanotechnology based drug delivery offers various advantages such as prolonged circulation time, delivery of cargo at desired site, improved bioavailability, reduced toxicity etc. over conventional chemotherapeutics. Abnormal characteristic features of TME play a paradoxical role in nanoparticulate drug delivery. Leaky vasculature, acidic and hypoxic conditions of TME helps in the accumulation of tailored nanoparticles whereas high interstitial pressure and dense stroma restrict the extravasation, homogenous distribution of nanocarriers in TME. This review mainly discusses the potential of nanotherapeutics in targeting TME by briefly discussing stromal components, therapeutic opportunities and barriers offered by TME for nanoparticulate drug delivery. Updated information on TME remodeling strategies for improved drug delivery and specific targeting of individual stromal components are also outlined.

Role of the Vanins-Myeloperoxidase Axis in Colorectal Carcinogenesis

The presence of chronic inflammation in the colonic mucosa leads to an increased risk of cancer. Among proteins involved in the regulation of mucosal inflammation and that may contribute both to structural damage of the intestinal mucosa and to intestinal carcinogenesis, there are myeloperoxidase (MPO) and vanins. The infiltration of colonic mucosa by neutrophils may promote carcinogenesis through MPO, a key enzyme contained in the lysosomes of neutrophils that regulates local inflammation and the generation of reactive oxygen species (ROS) and mutagenic species. The human vanin gene family consists of three genes: vanin-1, vanin-2 and vanin-3. All vanin molecules are pantetheinases, that hydrolyze pantetheine into pantothenic acid (vitamin B5), and cysteamine, a sulfhydryl compound. Vanin-1 loss confers an increased resistance to stress and acute intestinal inflammation, while vanin-2 regulates adhesion and transmigration of activated neutrophils. The metabolic product of these enzymes has a prominent role in the inflammation processes by affecting glutathione levels, inducing ulcers through a reduction in mucosal blood flow and oxygenation, decreasing local defense mechanisms, and in carcinogenesis by damaging DNA and regulating pathways involved in cell apoptosis, metabolism and growth, as Nrf2 and HIF-1α.

Tumour-associated macrophages activate migration and STAT3 in pancreatic ductal adenocarcinoma cells in co-cultures

OBJECTIVES

Tumour-associated macrophages participate in tumour development and progression. The aim of this study was to assess the interactions of pancreatic cancer cells and pro-inflammatory M1 and anti-inflammatory M2 macrophages, specifically their effect on pancreatic cancer cell migration and the changes in STAT-signalling.

METHODS

Monocytes were isolated from healthy subjects and differentiated into macrophages with M-CSF. The macrophages were polarized towards M1 by IL-12 and towards M2 by IL-10. We studied also the effect of pan-JAK/STAT-inhibitor P6. Macrophage polarization and STAT and NFkB-activation in both MiaPaCa-2 and macrophages were assessed by flow cytometry. We recorded the effect of co-culture on migration rate of pancreatic cancer cells MiaPaCa-2.

RESULTS

Macrophages increased the migration rate of pancreatic cancer cells. Co-culture activated STAT1, STAT3, STAT5, AKT, and NFkB in macrophages and STAT3 in MiaPaCa-2 cells. IL-12 polarized macrophages towards M1 and decreased the migration rate of pancreatic cancer cells in co-cultures as well as P6. IL-10 skewed macrophage polarization towards M2 and induced increase of pancreatic cancer cells in co-cultures.

CONCLUSION

Co-culture with macrophages increased pancreatic cancer cell migration and activated STAT3. It is possible to activate and deactivate migration of pancreatic cancer cells trough macrophage polarization.

Are Mast Cells MASTers in Cancer?

Prolonged low-grade inflammation or smoldering inflammation is a hallmark of cancer. Mast cells form a heterogeneous population of immune cells with differences in their ultra-structure, morphology, mediator content, and surface receptors. Mast cells are widely distributed throughout all tissues and are stromal components of the inflammatory microenvironment that modulates tumor initiation and development. Although canonically associated with allergic disorders, mast cells are a major source of pro-tumorigenic (e.g., angiogenic and lymphangiogenic factors) and antitumorigenic molecules (e.g., TNF-α and IL-9), depending on the milieu. In certain neoplasias (e.g., gastric, thyroid and Hodgkin's lymphoma) mast cells play a pro-tumorigenic role, in others (e.g., breast cancer) a protective role, whereas in yet others they are apparently innocent bystanders. These seemingly conflicting results suggest that the role of mast cells and their mediators could be cancer specific. The microlocalization (e.g., peritumoral vs intratumoral) of mast cells is another important aspect in the initiation/progression of solid and hematologic tumors. Increasing evidence in certain experimental models indicates that targeting mast cells and/or their mediators represent a potential therapeutic target in cancer. Thus, mast cells deserve focused consideration also as therapeutic targets in different types of tumors. There are many unanswered questions that should be addressed before we understand whether mast cells are an ally, adversary, or innocent bystanders in human cancers.

Stromal contributions to the carcinogenic process

Tumor-associated stromal cells are dynamic characters that endorse the carcinogenic process in a multitude of ways. The tumor microenvironment plays a crucial role throughout the tumor progression, which includes initiation, growth, invasion, and metastasis. The tumor microenvironment consists of cellular and non-cellular components. Tumor-associated stromal cell types include the microbiome, immune cells including macrophages, dendritic and T-cells, cells associated with blood and lymphatic vessels including pericytes and endothelial cells, fibroblasts, neuronal cells, and adipocytes. The non-cellular components of the microenvironment include matrix proteins and secreted factors. The development of therapies that target the mechanisms by which stromal cells contribute to successful tumorigenesis is major goal of upcoming cancer research. The purpose of this review is to present a comprehensive discussion of the role of each of the tumor-associated stromal cell types in the carcinogenic process with a special focus on target development and therapeutic intervention. © 2016 Wiley Periodicals, Inc.

Extracellular matrix and the myeloid-in-myeloma compartment: balancing tolerogenic and immunogenic inflammation in the myeloma niche

The last 10-15 years have witnessed a revolution in treating multiple myeloma, an incurable cancer of Ab-producing plasma cells. Advances in myeloma therapy were ushered in by novel agents that remodel the myeloma immune microenvironment. The first generation of novel agents included immunomodulatory drugs (thalidomide analogs) and proteasome inhibitors that target crucial pathways that regulate immunity and inflammation, such as NF-κB. This paradigm continued with the recent regulatory approval of mAbs (elotuzumab, daratumumab) that impact both tumor cells and associated immune cells. Moreover, recent clinical data support checkpoint inhibition immunotherapy in myeloma. With the success of these agents has come the growing realization that the myeloid infiltrate in myeloma lesions-what we collectively call the myeloid-in-myeloma compartment-variably sustains or deters tumor cells by shaping the inflammatory milieu of the myeloma niche and by promoting or antagonizing immune-modulating therapies. The myeloid-in-myeloma compartment includes myeloma-associated macrophages and granulocytes, dendritic cells, and myeloid-derived-suppressor cells. These cell types reflect variable states of differentiation and activation of tumor-infiltrating cells derived from resident myeloid progenitors in the bone marrow-the canonical myeloma niche-or myeloid cells that seed both canonical and extramedullary, noncanonical niches. Myeloma-infiltrating myeloid cells engage in crosstalk with extracellular matrix components, stromal cells, and tumor cells. This complex regulation determines the composition, activation state, and maturation of the myeloid-in-myeloma compartment as well as the balance between immunogenic and tolerogenic inflammation in the niche. Redressing this balance may be a crucial determinant for the success of antimyeloma immunotherapies.

Chlorogenic acid inhibits glioblastoma growth through repolarizating macrophage from M2 to M1 phenotype

Glioblastoma is an aggressive tumor that is associated with distinctive infiltrating microglia/macrophages populations. Previous studies demonstrated that chlorogenic acid (5-caffeoylquinic acid, CHA), a phenolic compound with low molecular weight, has an anti-tumor effect in multiple malignant tumors. In the present study, we focused on the macrophage polarization to investigate the molecular mechanisms behind the anti-glioma response of CHA in vitro and in vivo. We found that CHA treatment increased the expression of M1 markers induced by LPS/IFNγ, including iNOS, MHC II (I-A/I-E subregions) and CD11c, and reduced the expression of M2 markers Arg and CD206 induced by IL-4, resulting in promoting the production of apoptotic-like cancer cells and inhibiting the growth of tumor cells by co-culture experiments. The activations of STAT1 and STAT6, which are two crucial signaling events in M1 and M2-polarization, were significantly promoted and suppressed by CHA in macrophages, respectively. Furthermore, In G422 xenograft mice, CHA increased the proportion of CD11c-positive M1 macrophages and decreased the distribution of CD206-positive M2 macrophages in tumor tissue, consistent with the reduction of tumor weight observed in CHA-treated mice. Overall these findings indicated CHA as a potential therapeutic approach to reduce glioma growth through promoting M1-polarized macrophage and inhibiting M2 phenotypic macrophage.

M2 macrophages do not fly into a "RAGE"

Tumor-associated macrophages (TAMs) are key elements in orchestrating host responses inside tumor stroma. This population may undergo a polarized activation process, thus rendering a heterogeneous spectrum of phenotypes, where the classically activated type 1 macrophages (M1) and the alternative activated type 2 macrophages (M2) represent two extreme phenotypes. In this commentary, based on very recent research findings, we intend to highlight how complex could be the crosstalk among all components of tumor stroma, where the coexistence of non-natural partners may even skew the canonical responses that we can expect.

Imaging the Tumor Microenvironment

The tumor microenvironment consists of tumor, stromal, and immune cells, as well as extracellular milieu. Changes in numbers of these cell types and their environments have an impact on cancer growth and metastasis. Non-invasive imaging of aspects of the tumor microenvironment can provide important information on the aggressiveness of the cancer, whether or not it is metastatic, and can also help to determine early response to treatment. This chapter provides an overview on non-invasive in vivo imaging in humans and mouse models of various cell types and physiological parameters that are unique to the tumor microenvironment. Current clinical imaging and research investigation are in the areas of nuclear imaging (positron emission tomography (PET) and single photon emission computed tomography (SPECT)), magnetic resonance imaging (MRI) and optical (near infrared (NIR) fluorescence) imaging. Aspects of the tumor microenvironment that have been imaged by PET, MRI and/or optical imaging are tumor associated inflammation (primarily macrophages and T cells), hypoxia, pH changes, as well as enzymes and integrins that are highly prevalent in tumors, stroma and immune cells. Many imaging agents and strategies are currently available for cancer patients; however, the investigation of novel avenues for targeting aspects of the tumor microenvironment in pre-clinical models of cancer provides the cancer researcher with a means to monitor changes and evaluate novel treatments that can be translated into the clinic.

Group V Secreted Phospholipase A2 Induces the Release of Proangiogenic and Antiangiogenic Factors by Human Neutrophils

Secreted phospholipases A₂ (sPLA₂s) are extracellular enzymes that catalyze the release of free fatty acids and lysophospholipids from membrane phospholipids and also bind to different receptors (e.g., PLA₂R1 or integrins). To date, 12 mammalian sPLA₂s have been identified, which play a critical role in pathophysiological processes including inflammation and cancer. sPLA₂s activate immune cells such as human neutrophils (PMNs) by enzymatic activity- or receptor-mediated mechanisms. In addition, human PMNs synthesize and store human group V (hGV) and human group X (hGX) sPLA₂s in their granules, but only the former is released upon cellular activation. We investigated the effects of sPLA₂s on the release of proangiogenic and antiangiogenic factors by PMNs. We found that exogenous hGV and hGX sPLA₂s induce the release of vascular endothelial growth factor (VEGF)-A, angiopoietin 1 (Ang1), and CXCL8/IL-8. Only hGV induces the secretion of the antiangiogenic isoform of VEGF-A, namely, VEGF-A_165b. While the release of VEGF-A, Ang1, and CXCL8/IL-8 was likely mediated by hGV enzymatic activity and/or binding to PLA₂R1 and heparan sulfate proteoglycans, the release of VEGF-A_165b requires the interaction with α_Vβ₃ and α₄β₁ integrins. We also provide evidence that endogenous hGV released by N-formyl-met-leu-phe (fMLF)-activated PMNs is involved in the release of angiogenic factors. The translational relevance of these data is supported by our findings that hGV expression is increased in human samples of lung cancer which are infiltrated by PMNs. Overall, our results suggest that the hGV-neutrophil axis may play a relevant role in the modulation of cancer-related inflammation and angiogenesis.

Driving Cancer Tumorigenesis and Metastasis Through UPR Signaling

In the tumor microenvironment, cancer cells encounter both external and internal factors that can lead to the accumulation of improperly folded proteins in the Endoplasmic Reticulum (ER) lumen, thus causing ER stress. When this happens, an adaptive mechanism named the Unfolded Protein Response (UPR) is triggered to help the cell cope with this change and restore protein homeostasis in the ER. Sequentially, one would expect that the activation of the three UPR branches, driven namely by IRE1, PERK, and ATF6, are crucial for the adaptation of cancer cells to the changing environment and thus for their survival and further propagation. Indeed, in the last few years, an increasing amount of studies has shown the implication of UPR signaling in different aspects of carcinogenesis and tumor progression. Features such as sustaining proliferation and resistance to cell death, genomic instability, altered metabolism, increased inflammation and tumor-immune infiltration, invasion and metastasis, and angiogenesis, defined as "the hallmarks of cancer", can be regulated by the UPR machinery. At the same time, new potential therapeutic interventions applicable to different kinds of cancers are being revealed. In order to describe the emerging role of UPR in cancer biology, these are the points that will be discussed in this chapter.

All Trans Retinoic Acid, Transforming Growth Factor β and Prostaglandin E2 in Mouse Plasma Synergize with Basophil-Secreted Interleukin-4 to M2 Polarize Murine Macrophages

In previous studies we found that macrophages (MФs) from SH2-containing inositol-5'-phosphatase (SHIP) deficient mice are M2 polarized while their wild type (WT) counterparts are M1 polarized and that this difference in MФ phenotype can be recapitulated during in vitro derivation from bone marrow if mouse plasma (MP), but not fetal calf serum, is added to standard M-CSF-containing cultures. In the current study we investigated the mechanism by which MP skews SHIP-/- but not +/+ MФs to an M2 phenotype. Our results suggest that SHIP-/- basophils constitutively secrete higher levels of IL-4 than SHIP+/+ basophils and this higher level of IL-4 is sufficient to skew both SHIP+/+ and SHIP-/- MФs to an M2 phenotype, but only when MP is present to increase the sensitivity of the MФs to this level of IL-4. MP increases the IL-4 sensitivity of both SHIP+/+ and -/- MФs not by increasing cell surface IL-4 or CD36 receptor levels, but by triggering the activation of Erk and Akt and the production of ROS, all of which play a critical role in sensitizing MФs to IL-4-induced M2 skewing. Studies to identify the factor(s) in MP responsible for promoting IL-4-induced M2 skewing suggests that all-trans retinoic acid (ATRA), TGFβ and prostaglandin E2 (PGE2) all play a role. Taken together, these results indicate that basophil-secreted IL-4 plays an essential role in M2 skewing and that ATRA, TGFβ and PGE2 within MP collaborate to dramatically promote M2 skewing by acting directly on MФs to increase their sensitivity to IL-4.

Pro-Tumoral Inflammatory Myeloid Cells as Emerging Therapeutic Targets

Since the observation of Virchow, it has long been known that the tumor microenvironment constitutes the soil for the infiltration of inflammatory cells and for the release of inflammatory mediators. Under certain circumstances, inflammation remains unresolved and promotes cancer development. Here, we review some of these indisputable experimental and clinical evidences of cancer related smouldering inflammation. The most common myeloid infiltrate in solid tumors is composed of myeloid-derived suppressor cells (MDSCs) and tumor-associated macrophages (TAMs). These cells promote tumor growth by several mechanisms, including their inherent immunosuppressive activity, promotion of neoangiogenesis, mediation of epithelial-mesenchymal transition and alteration of cellular metabolism. The pro-tumoral functions of TAMs and MDSCs are further enhanced by their cross-talk offering a myriad of potential anti-cancer therapeutic targets. We highlight these main pro-tumoral mechanisms of myeloid cells and give a general overview of their phenotypical and functional diversity, offering examples of possible therapeutic targets. Pharmacological targeting of inflammatory cells and molecular mediators may result in therapies improving patient condition and prognosis. Here, we review experimental and clinical findings on cancer-related inflammation with a major focus on creating an inventory of current small molecule-based therapeutic interventions targeting cancer-related inflammatory cells: TAMs and MDSCs.

PLD-Specific Small-Molecule Inhibitors Decrease Tumor-Associated Macrophages and Neutrophils Infiltration in Breast Tumors and Lung and Liver Metastases

Phospholipase D-2 (PLD2) has a key role in breast cancer formation and metastasis formation with PLD small inhibitors reducing primary tumor growth. This study aimed to evaluate the importance of targeting PLD on the tumor microenvironment. We provide evidence about the beneficial effect of PLD inhibitors [FIPI (dual PLD1/PLD2) or VU0155072-2 (PLD2 inhibitor)] on avoiding infiltration of tumor-helping macrophages and neutrophils. Tumor growth and metastasis within the primary tumors had low (<20% over controls) PLD enzyme activity. Unexpectedly, we found that the inhibitors also affected PLD2 gene expression and protein albeit at a lesser extent. The later could indicate that targeting both the actual PLD enzyme and its activity could be beneficial for potential cancer treatments in vivo. F4/80 and Ly6G staining of macrophages and neutrophils, respectively, and Arg1 staining data were consistent with M2 and N2 polarization. NOS2 staining increased in xenotransplants upon treatment with PLD2 inhibitors suggesting the novel observation that an increased recruitment of M1 macrophages occurred in primary tumors. PLD inhibitor-treated primary tumors had large, fragile, necrotic areas that were Arg1+ for M2 macrophages. The xenotransplants also caused the formation of large F4/80+ and Ly6G+ (>100 μm) clusters in lungs. However, PLD inhibitors, particularly FIPI, were able to diminish leukocyte presence. Ex vivo chemotaxis and PLD activity of peripheral blood neutrophils (PMN) and peritoneal macrophages was also determined. Whereas PMN had impaired functionality, macrophages did not. This significantly increased ("emboldened") macrophage function was due to PLD inhibition. Since tumor-associated leukocytes in primary tumors and metastases were targeted via PLD inhibition, we posit that these inhibitors have a key role in cancer regression, while still affording an appropriate inflammatory response at least from off-site innate immunity macrophages.

The Complexity of Targeting PI3K-Akt-mTOR Signalling in Human Acute Myeloid Leukaemia: The Importance of Leukemic Cell Heterogeneity, Neighbouring Mesenchymal Stem Cells and Immunocompetent Cells

Therapeutic targeting of PI3K-Akt-mTOR is considered a possible strategy in human acute myeloid leukaemia (AML); the most important rationale being the proapoptotic and antiproliferative effects of direct PI3K/mTOR inhibition observed in experimental studies of human AML cells. However, AML is a heterogeneous disease and these effects caused by direct pathway inhibition in the leukemic cells are observed only for a subset of patients. Furthermore, the final effect of PI3K-Akt-mTOR inhibition is modulated by indirect effects, i.e., treatment effects on AML-supporting non-leukemic bone marrow cells. In this article we focus on the effects of this treatment on mesenchymal stem cells (MSCs) and monocytes/macrophages; both these cell types are parts of the haematopoietic stem cell niches in the bone marrow. MSCs have unique membrane molecule and constitutive cytokine release profiles, and mediate their support through bidirectional crosstalk involving both cell-cell contact and the local cytokine network. It is not known how various forms of PI3K-Akt-mTOR targeting alter the molecular mechanisms of this crosstalk. The effect on monocytes/macrophages is also difficult to predict and depends on the targeted molecule. Thus, further development of PI3K-Akt-mTOR targeting into a clinical strategy requires detailed molecular studies in well-characterized experimental models combined with careful clinical studies, to identify patient subsets that are likely to respond to this treatment.

Controversial role of mast cells in skin cancers

Cancer development is a multistep process characterized by genetic and epigenetic alterations during tumor initiation and progression. The stromal microenvironment can promote tumor development. Mast cells, widely distributed throughout all tissues, are a stromal component of many solid and haematologic tumors. Mast cells can be found in human and mouse models of skin cancers such as melanoma, basal and squamous cell carcinomas, primary cutaneous lymphomas, haemangiomas and Merkel cell carcinoma. However, human and animal studies addressing potential functions of mast cells and their mediators in skin cancers have provided conflicting results. In several studies, mast cells play a pro-tumorigenic role, whereas in others, they play an anti-tumorigenic role. Other studies have failed to demonstrate a clear role for tumor-associated mast cells. Many unanswered questions need to be addressed before we understand whether tumor-associated mast cells are adversaries, allies or simply innocent bystanders in different types and subtypes of skin cancers.

Acute myeloid leukemia cells polarize macrophages towards a leukemia supporting state in a Growth factor independence 1 dependent manner

The growth of malignant cells is not only driven by cell-intrinsic factors, but also by the surrounding stroma. Monocytes/Macrophages play an important role in the onset and progression of solid cancers. However, little is known about their role in the development of acute myeloid leukemia, a malignant disease characterized by an aberrant development of the myeloid compartment of the hematopoietic system. It is also unclear which factors are responsible for changing the status of macrophage polarization, thus supporting the growth of malignant cells instead of inhibiting it. We report herein that acute myeloid leukemia leads to the invasion of acute myeloid leukemia-associated macrophages into the bone marrow and spleen of leukemic patients and mice. In different leukemic mouse models, these macrophages support the in vitro expansion of acute myeloid leukemia cell lines better than macrophages from non-leukemic mice. The grade of macrophage infiltration correlates in vivo with the survival of the mice. We found that the transcriptional repressor Growth factor independence 1 is crucial in the process of macrophage polarization, since its absence impedes macrophage polarization towards a leukemia supporting state and favors an anti-tumor state both in vitro and in vivo These results not only suggest that acute myeloid leukemia-associated macrophages play an important role in the progression of acute myeloid leukemia, but also implicate Growth factor independence 1 as a pivotal factor in macrophage polarization. These data may provide new insights and opportunities for novel therapies for acute myeloid leukemia.

Elucidating drivers of oral epithelial dysplasia formation and malignant transformation to cancer using RNAseq

Oral squamous cell carcinoma (OSCC) is a prevalent cancer with poor prognosis. Most OSCC progresses via a non-malignant stage called dysplasia. Effective treatment of dysplasia prior to potential malignant transformation is an unmet clinical need. To identify markers of early disease, we performed RNA sequencing of 19 matched HPV negative patient trios: normal oral mucosa, dysplasia and associated OSCC. We performed differential gene expression, principal component and correlated gene network analysis using these data. We found differences in the immune cell signatures present at different disease stages and were able to distinguish early events in pathogenesis, such as upregulation of many HOX genes, from later events, such as down-regulation of adherens junctions. We herein highlight novel coding and non-coding candidates for involvement in oral dysplasia development and malignant transformation, and speculate on how our findings may guide further translational research into the treatment of oral dysplasia.

Tumor-associated neutrophils display a distinct N1 profile following TGFβ modulation: A transcriptomics analysis of pro- vs. antitumor TANs

It is becoming increasingly clear that tumor-associated neutrophils (TANs) play an important role in cancer biology, through direct impact on tumor growth and by recruitment of other cells types into the tumor. The function of neutrophils in cancer has been the subject of seemingly contradicting reports, pointing toward a dual role played by TANs in tumor progression. The existence of multiple neutrophil subsets, as well as phenotypic modulation of the neutrophils by various factors in the tumor microenvironment, has been shown. TGFβ plays a significant role in the determination of neutrophils' phenotype, by shifting the balance from an antitumor (N1) toward a more permissive (N2) phenotype. The full range of mechanisms responsible for the pro- vs. antitumor effects of TANs has not yet been elucidated. Therefore, the ability to identify the different neutrophil subpopulations in the tumor is critical in order to understand TANs evolution and contribution throughout tumor progression. Using a transcriptomic approach, we identified alternations in gene expression profile following TGFβ inhibition. We show that N1 and N2 TANs represent distinct subpopulations with different transcriptional signatures and both differ from naive bone marrow neutrophils. The analysis highlights a clear difference in pathways involved in neutrophil function such as cytoskeletal organization and antigen presentation, as well as alterations in chemokine profile, eventually affecting their effect on tumor cells and tumor growth. These data highlights several potential new pathways and mechanisms by which neutrophils can influence both the tumor cells and the adaptive immune system.

Prognostic Significance of the Preoperative Lymphocyte to Monocyte Ratio in Patients With Stage I Non-Small Cell Lung Cancer Undergoing Complete Resection

In this study, we investigated the correlation between lymphocyte to monocyte ratio (LMR) and clinical outcomes in stage I non-small cell lung cancer (NSCLC) patients. A total of 439 stage I NSCLC patients were enrolled in this study. Multivariate analyses identified LMR as an independent prognostic factor for recurrence-free survival and overall survival (hazard ratio (HR: 0.469, 95% Confidence Interval (CI): 0.325-0.677, and p < 0.001, and HR: 0.478, 95% CI: 0.332-0.688, and p < 0.001; respectively). Compared with the high LMR group, the proportion of patients who developed distant metastasis was significantly higher in the low LMR group.

Changes in peripheral blood T, NK and B cells and thymus function in patients with HBV-related primary liver cancer

AIM: To explore changes in the distribution of peripheral blood T, NK and B cells and thymus function in the occurrence and progression of hepatitis B virus-related primary liver cancer (HBV-PLC).

METHODS: Clinical and laboratory data of 73 HBV-PLV patients, 50 liver cirrhosis (LC) patients and 37 chronic hepatitis B (CHB) patients were collected at Beijing Ditan Hospital, Capital Medical University. The distribution of CD3⁺ T, CD4⁺ T, CD8⁺ T, CD3-CD16⁺CD56⁺ NK, CD3-CD19⁺ B cells and the expression of CD31, CD45RA on T cells were detected in peripheral blood of all patients by flow cytometry.

RESULTS: Compared with CHB and LC patients, the percentage and absolute number of lymphocytes declined in HBV-PLC patients (P < 0.001). Compared with LC patients, the numbers of T, CD4⁺ T, CD8⁺ T, B (P < 0.001), and NK cells (P = 0.011) significantly decreased in HBV-PLC patients. With regard to Child-Pugh, Okuda, and BCLC stages, the numbers of lymphocytes, T, CD4⁺ T, and CD8⁺ T cells were significantly lower in advanced stages than in early stages (P < 0.05).

CONCLUSION: The immune cells that have anti-tumor effects decrease in the peripheral blood of HBV-PLC patients, which may be due to the reduced thymus function.

CD45 Phosphatase Inhibits STAT3 Transcription Factor Activity in Myeloid Cells and Promotes Tumor-Associated Macrophage Differentiation

Recruitment of monocytic myeloid-derived suppressor cells (MDSCs) and differentiation of tumor-associated macrophages (TAMs) are the major factors contributing to tumor progression and metastasis. We demonstrated that differentiation of TAMs in tumor site from monocytic precursors was controlled by downregulation of the activity of the transcription factor STAT3. Decreased STAT3 activity was caused by hypoxia and affected all myeloid cells but was not observed in tumor cells. Upregulation of CD45 tyrosine phosphatase activity in MDSCs exposed to hypoxia in tumor site was responsible for downregulation of STAT3. This effect was mediated by the disruption of CD45 protein dimerization regulated by sialic acid. Thus, STAT3 has a unique function in the tumor environment in controlling the differentiation of MDSC into TAM, and its regulatory pathway could be a potential target for therapy.

EGFR regulates the development and microarchitecture of intratumoral angiogenic vasculature capable of sustaining cancer cell intravasation

Many malignant characteristics of cancer cells are regulated through pathways induced by the tyrosine kinase activity of the epidermal growth factor receptor (EGFR). Herein, we show that besides directly affecting the biology of cancer cells per se, EGFR also regulates the primary tumor microenvironment. Specifically, our findings demonstrate that both the expression and signaling activity of EGFR are required for the induction of a distinct intratumoral vasculature capable of sustaining tumor cell intravasation, a critical rate-limiting step in the metastatic cascade. An intravasation-sustaining mode of intratumoral angiogenic vessels depends on high levels of tumor cell EGFR and the interplay between EGFR-regulated production of interleukin 8 by tumor cells, interleukin-8–induced influx of tumor-infiltrating neutrophils delivering their unique matrix metalloproteinase-9, and neutrophil matrix metalloproteinase-9–dependent release of the vascular permeability and endothelial growth factor, VEGF. Our data indicate that through VEGF-mediated disruption of endothelial layer integrity and increase of intratumoral vasculature permeability, EGFR activity significantly facilitates active intravasation of cancer cells. Therefore, this study unraveled an important but overlooked function of EGFR in cancer, namely, its ability to create an intravasation-sustaining microenvironment within the developing primary tumor by orchestrating several interrelated processes required for the initial steps of cancer metastasis through vascular routes. Our findings also suggest that EGFR-targeted therapies might be more effective when implemented in cancer patients with early-staged primary tumors containing a VEGF-dependent angiogenic vasculature. Accordingly, early EGFR inhibition combined with various anti-VEGF approaches could synergistically suppress tumor cell intravasation through inhibiting the highly permeable angiogenic vasculature induced by EGFR-overexpressing aggressive cancer cells.

Strategies targeting the IL-4/IL-13 axes in disease

IL-4 and IL-13 are pleiotropic Th2 cytokines produced by a wide variety of different cell types and responsible for a broad range of biology and functions. Physiologically, Th2 cytokines are known to mediate host defense against parasites but they can also trigger disease if their activities are dysregulated. In this review we discuss the rationale for targeting the IL-4/IL-13 axes in asthma, atopic dermatitis, allergic rhinitis, COPD, cancer, inflammatory bowel disease, autoimmune disease and fibrotic disease as well as evaluating the associated clinical data derived from blocking IL-4, IL-13 or IL-4 and IL-13 together.

The immune network in thyroid cancer

The immune system plays critical roles in tumor prevention, but also in its initiation and progression. Tumors are subjected to immunosurveillance, but cancer cells generate an immunosuppressive microenvironment that favors their escape from immune-mediated elimination. During chronic inflammation, immune cells can contribute to the formation and progression of tumors by producing mitogenic, prosurvival, proangiogenic and lymphangiogenic factors. Thyroid cancer is the most frequent type of endocrine neoplasia and is the most rapidly increasing cancer in the US. In this review, we discuss recent findings on how different immune cells and mediators can contribute to thyroid cancer development and progression.

Tumor-Associated Neutrophils Recruit Macrophages and T-Regulatory Cells to Promote Progression of Hepatocellular Carcinoma and Resistance to Sorafenib

BACKGROUND & AIMS

Neutrophils can either promote or inhibit tumor progression, depending on the tumor microenvironment, via release of cytokines. Neither the factors produced by tumor-associated neutrophils (TANs) nor their effects on tumor progression have been characterized. We investigated the roles of TANs in progression of hepatocellular carcinoma (HCC) using cell lines and immune cells isolated from patients.

METHODS

We performed studies with HepG2, PLC/PRF/5, MHCC97H, and HCCLM3 human and Hepa1-6 and H22 mouse HCC cell lines; expression of chemokines and cytokines were knocked down with small hairpin RNAs. Cells were analyzed in chemotaxis assays and as growth as tumors in mice. HCC tissues and peripheral blood were collected from 20 patients undergoing curative resection or 20 healthy individuals (controls) in 2012 at Zhongshan Hospital in China. TANs and peripheral blood neutrophils (PBNs) were isolated and exposed to conditioned media from HCC cell lines; reverse-transcription polymerase chain reaction was used to quantify the expression of cytokines and chemokines. We collected neutrophils from another 60 patients undergoing curative resection for HCC in 2012 to measure the production of C-C motif chemokine ligand 2(CCL2) and CCL17. Patients were followed up until March 15, 2014. For immunohistochemical analyses, we collected HCC tissues and paired, adjacent, nontumor cirrhotic liver tissues from 832 HCC patients undergoing curative resection from 2006 through 2008. All patients were followed up until March 15, 2013. To study the effects of sorafenib, we collected clinical and pathology data from 46 patients who underwent curative resection in 2010.

RESULTS

CCL2 and CCL17 were the cytokines most highly expressed by TANs and HCC cell-activated PBNs. Levels of CCL2 and CCL17 messenger RNAs and proteins were significantly higher in TANs than in PBNs, and increased in patients with HCC recurrence. CCL2 and CCL17 messenger RNA and proteins also increased when PBNs were exposed to conditioned media from HCC cell lines. Immunohistochemical analysis of a tissue microarray showed that CCL2+ and CCL17+ cells, which also expressed the neutrophil marker CD66b, were distributed throughout the HCC stroma, but not in tumor cells or the adjacent nontumor liver cells. The number of CCL2+ or CCL17+ TANs correlated with tumor size, microvascular invasion, tumor encapsulation, tumor differentiation, and stage. Patients whose tumors had lower levels of CCL2+ or CCL17+ cells had longer survival times than those with higher numbers of these cells. TAN-conditioned media, as well as recombinant CCL2 and CCL17, increased the migratory activity of the macrophages and T-regulatory (Treg) cells from patients or mice with HCC to a greater extent that PBN-conditioned media. Neutralizing antibodies against CCL2 and CCL17, or their receptors C-C chemokine receptor 2 and C-C chemokine receptor 4, reduced the migratory activities of macrophage and Treg cells. HCC cell lines injected into mice formed larger tumors when they were co-injected with TANs and formed more pulmonary metastases; these tumors were infiltrated by Ly6G+ cells, F4/80+ macrophages, and Foxp3+ Treg cells. In a phosphokinase array of human PBNs, levels of phosphorylated AKT and P38 increased after exposure to conditioned media from all 4 HCC cell types. Pharmacologic inhibitors of AKT and P38 inhibited secretion of CCL2 and CCL17 by these PBNs. In tumor-bearing mice, sorafenib increased the numbers of TANs and levels of CCL2 and CCL17 in tumors. HCC tissues from patients who received sorafenib before surgery contained more TANs than tissues from patients who did not receive sorafenib. In knockdown cells, HCC cell-derived CXCL5 was the strongest effector of neutrophil migration under hypoxic conditions. In mice, the combination of sorafenib and TAN depletion inhibited tumor growth and neovascularization to a greater extent than sorafenib alone.

CONCLUSIONS

TANs recruit macrophages and Treg cells to HCCs to promote their growth, progression, and resistance to sorafenib.

IL-8-Positive Tumor-Infiltrating Inflammatory Cells Are a Novel Prognostic Marker in Pancreatic Ductal Adenocarcinoma Patients

OBJECTIVES

Tumor-infiltrating inflammatory cells (TIICs) in pancreatic ductal adenocarcinoma (PDAC) are reported to initiate and exacerbate invasion and metastasis. Interleukin-8 (IL-8), a proinflammatory cytokine, is expressed in both neoplastic cells and TIICs in PDAC tissues and increased in patient serum. The aim of this study is to evaluate the values of IL-8 expression profiles in tumor tissues and predict the source of serum IL-8 in PDAC patients.

METHODS

We used 2 independent groups of PDAC patient samples that included 240 cases. Tissue expression profiles of cytokines were evaluated with immunohistochemistry and serum levels with human IL-8 assay. The prognostic values of the variables were assessed by Kaplan-Meier or Cox regression analysis.

RESULTS

Higher levels of IL-8-positive TIICs but not tumor cells in PDAC patients correlated with worse prognosis (P = 0.009) and higher blood serum IL-8 levels (P = 0.002). Controlling other independent factors, the relative hazard ratio for PDAC with higher IL-8-positive TIIC levels compared with those with lower TIIC levels was 1.588 (95% confidence interval, 1.04-2.42).

CONCLUSIONS

Higher IL-8-positive TIIC levels in PDAC tumors indicate poorer prognosis and positively correlate with serum IL-8 concentrations and vice versa. These data suggested that IL-8 might have a potential target for PDAC therapies.

Guidance Molecule SEMA3A Restricts Tumor Growth by Differentially Regulating the Proliferation of Tumor-Associated Macrophages

Accumulation of tumor-associated macrophages (TAM) correlates with malignant progression, immune suppression, and poor prognosis. In this study, we defined a critical role for the cell-surface guidance molecule SEMA3A in differential proliferative control of TAMs. Tumor cell-derived SEMA3A restricted the proliferation of protumoral M2 macrophages but increased the proliferation of antitumoral M1, acting through the SEMA3A receptor neuropilin 1. Expansion of M1 macrophages in vivo enhanced the recruitment and activation of natural killer (NK) cells and cytotoxic CD8(+) T cells to tumors, inhibiting their growth. In human breast cancer specimens, we found that immunohistochemical levels of SEMA3A correlated with the expression of genes characteristic of M1 macrophages, CD8(+) T cells, and NK cells, while inversely correlating with established characters of malignancy. In summary, our results illuminate a mechanism whereby the TAM phenotype is controlled and identify the cell-surface molecule SEMA3A as a candidate for therapeutic targeting. Cancer Res; 76(11); 3166-78. ©2016 AACR.

Human lung-resident macrophages express CB1 and CB2 receptors whose activation inhibits the release of angiogenic and lymphangiogenic factors

Macrophages are pivotal effector cells in immune responses and tissue remodeling by producing a wide spectrum of mediators, including angiogenic and lymphangiogenic factors. Activation of cannabinoid receptor types 1 and 2 has been suggested as a new strategy to modulate angiogenesis in vitro and in vivo. We investigated whether human lung-resident macrophages express a complete endocannabinoid system by assessing their production of endocannabinoids and expression of cannabinoid receptors. Unstimulated human lung macrophage produce 2-arachidonoylglycerol,N-arachidonoyl-ethanolamine,N-palmitoyl-ethanolamine, and N-oleoyl-ethanolamine. On LPS stimulation, human lung macrophages selectively synthesize 2-arachidonoylglycerol in a calcium-dependent manner. Human lung macrophages express cannabinoid receptor types 1 and 2, and their activation induces ERK1/2 phosphorylation and reactive oxygen species generation. Cannabinoid receptor activation by the specific synthetic agonists ACEA and JWH-133 (but not the endogenous agonist 2-arachidonoylglycerol) markedly inhibits LPS-induced production of vascular endothelial growth factor-A, vascular endothelial growth factor-C, and angiopoietins and modestly affects IL-6 secretion. No significant modulation of TNF-α or IL-8/CXCL8 release was observed. The production of vascular endothelial growth factor-A by human monocyte-derived macrophages is not modulated by activation of cannabinoid receptor types 1 and 2. Given the prominent role of macrophage-assisted vascular remodeling in many tumors, we identified the expression of cannabinoid receptors in lung cancer-associated macrophages. Our results demonstrate that cannabinoid receptor activation selectively inhibits the release of angiogenic and lymphangiogenic factors from human lung macrophage but not from monocyte-derived macrophages. Activation of cannabinoid receptors on tissue-resident macrophages might be a novel strategy to modulate macrophage-assisted vascular remodeling in cancer and chronic inflammation.

Modifying the tumor microenvironment using nanoparticle therapeutics

Treatment of cancer has come a long way from the initial 'radical surgeries' to the multimodality treatments. For the major part of the last century, cancer was considered as a monocellular disorder, and treatment strategies were designed according to that hypothesis. However, the mortality rate from cancer continued to be high and a comprehensive treatment remained elusive. Recent progress in research has demonstrated that tumors are a complex network of neoplastic and non-neoplastic cells. The non-neoplastic cells, which are collectively called stroma, assist in tumor survival and progression. It has been shown that disrupting the tumor-stromal balance leads to significant effects on the tumor survival, and effective treatment can be achieved by targeting one or more of the stromal components. In this review, we summarize the roles of various stromal components in promoting tumor progression, and discuss innovative nanoparticle-mediated drug targeting strategies for stromal depletion and the subsequent effects on the tumors. Perspectives and the future directions are also provided. WIREs Nanomed Nanobiotechnol 2016, 8:891-908. doi: 10.1002/wnan.1406 For further resources related to this article, please visit the WIREs website.

Jacalin-Activated Macrophages Exhibit an Antitumor Phenotype

Tumor-associated macrophages (TAMs) have an ambiguous and complex role in the carcinogenic process, since these cells can be polarized into different phenotypes (proinflammatory, antitumor cells or anti-inflammatory, protumor cells) by the tumor microenvironment. Given that the interactions between tumor cells and TAMs involve several players, a better understanding of the function and regulation of TAMs is crucial to interfere with their differentiation in attempts to skew TAM polarization into cells with a proinflammatory antitumor phenotype. In this study, we investigated the modulation of macrophage tumoricidal activities by the lectin jacalin. Jacalin bound to macrophage surface and induced the expression and/or release of mainly proinflammatory cytokines via NF-κB signaling, as well as increased iNOS mRNA expression, suggesting that the lectin polarizes macrophages toward the antitumor phenotype. Therefore, tumoricidal activities of jacalin-stimulated macrophages were evaluated. High rates of tumor cell (human colon, HT-29, and breast, MCF-7, cells) apoptosis were observed upon incubation with supernatants from jacalin-stimulated macrophages. Taken together, these results indicate that jacalin, by exerting a proinflammatory activity, can direct macrophages to an antitumor phenotype. Deep knowledge of the regulation of TAM functions is essential for the development of innovative anticancer strategies.

Comparison of the prognostic value of measures of the tumor inflammatory cell infiltrate and tumor-associated stroma in patients with primary operable colorectal cancer

The aim of the present study was to compare the clinical utility of two measures of the inflammatory cell infiltrate - a H&E-based assessment of the generalized inflammatory cell infiltrate (the Klintrup-Mäkinen (KM) grade), and an immunohistochemistry-based assessment of combined CD3⁺ and CD8⁺ T-cell density (the "Immunoscore"), in conjunction with assessment of the tumor stroma percentage (TSP) in patients undergoing resection of stage I-III colorectal cancer (CRC). Two hundred and forty-six patients were identified from a prospectively maintained database of CRC resections in a single surgical unit. Assessment of KM grade and TSP was performed using full H&E sections. CD3⁺ and CD8⁺ T-cell density was assessed on full sections and the Immunoscore calculated. KM grade and Immunoscore were strongly associated (p < 0.001). KM grade stratified cancer-specific survival (CSS) from 88% to 66% (p = 0.002) and Immunoscore from 93% to 61% (p < 0.001). Immunoscore further stratified survival of patients independent of KM grade from 94% (high KM, Im4) to 60% (low KM, Im0/1). Furthermore, TSP stratified survival of patients with a weak inflammatory cell infiltrate (low KM: from 75% to 47%; Im0/1: from 71% to 38%, both p < 0.001) but not those with a strong inflammatory infiltrate. On multivariate analysis, only Immunoscore (HR 0.44, p < 0.001) and TSP (HR 2.04, p < 0.001) were independently associated with CSS. These results suggest that the prognostic value of an immunohistochemistry-based assessment of the inflammatory cell infiltrate is superior to H&E-based assessment in patients undergoing resection of stage I-III CRC. Furthermore, assessment of the tumor-associated stroma, using TSP, further improves prediction of outcome.

HMGB1 enhances the protumoral activities of M2 macrophages by a RAGE-dependent mechanism

The monocyte-macrophage lineage shows a high degree of diversity and plasticity. Once they infiltrate tissues, they may acquire two main functional phenotypes, being known as the classically activated type 1 macrophages (M1) and the alternative activated type 2 macrophages (M2). The M1 phenotype can be induced by bacterial products and interferon-γ and exerts a cytotoxic effect on cancer cells. Conversely, the alternatively activated M2 phenotype is induced by Il-4/IL13 and promotes tumor cell growth and vascularization. Although receptor for advanced glycation end-products (RAGE) engagement in M1 macrophages has been reported by several groups to promote inflammation, nothing is known about the functionality of RAGE in M2 macrophages. In the current study, we demonstrate that RAGE is equally expressed in both macrophage phenotypes and that RAGE activation by high-mobility group protein box1 (HMGB1) promotes protumoral activities of M2 macrophages. MKN45 cells co-cultured with M2 macrophages treated with HMGB1 at different times displayed higher invasive abilities. Additionally, conditioned medium from HMGB1-treated M2 macrophages promotes angiogenesis in vitro. RAGE-targeting knockdown abrogates these activities. Overall, the present findings suggest that HMGB1 may contribute, by a RAGE-dependent mechanism, to the protumoral activities of the M2 phenotype.

Prognostic value of polarized macrophages in patients with hepatocellular carcinoma after curative resection

As the most predominant tumour‐infiltrating immune cells, tumour‐associated macrophages (TAMs) are significant for fostering tumour growth, progression and metastasis. CD68‐positive TAMs display dissimilarly polarized programmes comprising CD11c‐positive pro‐inflammatory macrophages (M1) and CD206‐positive immunosuppressive macrophages (M2). The aim of this study is to determine the prognostic significance of diametrically polarized TAMs in hepatocellular carcinoma (HCC) and their application to risk stratification of patients according to their specific prognostic values. This study included 80 consecutive patients with HCC, and we evaluated diametrically polarized functional status of macrophages by immunohistochemical staining of CD68, CD11c and CD206. Prognostic values and clinicopathologic features were assessed in these patients. High versus low CD11c‐positive TAM density (P = 0.005) and low versus high CD206‐positive TAM density (P = 0.002) were associated with better overall survival, whereas CD68‐positive TAM density had no prognostic significance (low versus high, P = 0.065). Furthermore, the presence of these positive staining macrophages did not show any prognostic significance for recurrence‐free survival (all P > 0.05). Multivariate Cox regression analysis identified CD11c‐positive and CD206‐positive TAMs as an independent prognostic factor (P < 0.001, P = 0.031, respectively). Intratumoural infiltration of diametrically polarized TAMs, a novel identified independent prognostic factor for survival in patients with HCC, could be combined with the TNM stage and the Barcelona Clinic Liver Cancer stage to improve a risk stratification system.

Cancer as a changed tissue's way of life (when to treat, when to watch and when to think)

The profound scientific and commercial success of molecular biology, the progress of 'cancer gene' investigation technologies, together, pushed forward the postulate that genes explain 'everything'. Yet, during the last few years the microenvironments of solid tumors have emerged as key modulators of initiation, progression and metastasis and as essential to the therapeutic response. In the present review, we provide a synthetic examination of the main traits of cells embedded into the cancer stroma and emphasize several evidences that all components of the tumor tissue cooperate in space and time. Then we turn to discuss the epitheliocentric somatic mutational view and other new paradigms assuming that disturbed tissue interactions among cell populations are critical to cancer causation, growth and spread.

The Role of Tumor-Infiltrating Lymphocytes in Development, Progression, and Prognosis of Non-Small Cell Lung Cancer

A malignant tumor is not merely an accumulation of neoplastic cells, but constitutes a microenvironment containing endothelial cells, fibroblasts, structural components, and infiltrating immune cells that impact tumor development, invasion, metastasis, and outcome. Hence, the evolution of cancers reflects intricate cellular and molecular interactions between tumor cells and constituents of the tumor microenvironment. Recent studies have shed new light on this complex interaction between tumor and host immune cells and the resulting immune response. The composition of the immune microenvironment differs across patients as well as in cancers of the same type, including various populations of T cells, B cells, dendritic cells, natural killer cells, myeloid-derived suppressor cells, neutrophils, and macrophages. The type, density, location, and organization of immune cells within solid tumors define the immune contexture, which has proved to be a major determinant of tumor characteristics and patient outcome. Lung cancer consists mostly of non-small cell lung cancer (85%); it is our most deadly malignant disease, with the 5-year survival rate being merely 15%. This review focuses on the immune contexture; the tumor-suppressing roles of tumor-infiltrating lymphocytes; and the relevance of this immune contexture for cancer diagnostics, prognostication, and treatment allocation, with an emphasis on non-small cell lung cancer.

Staphylococcus epidermidis and biofilm-associated neutrophils in chronic rhinosinusitis. A pilot study

A key role of bacterial biofilm in the pathogenesis of chronic rhinosinusitis (CRS) with (CRSwNP) and without nasal polyps (CRSsNP) is commonly accepted. However, the impact of some bacterial species isolated from inflamed sinus mucosa on biofilm formation is unclear. In particular, the role of Staphylococcus epidermidis as aetiological agents of CRS is controversial. Moreover, the effect of biofilm formation on neutrophil infiltration and activity in CRSwNP calls for explanation. In this study, biofilms were found in three of 10 patients (mean age = 46 ± 14) with CRS undergoing endoscopic sinus surgery by means of scanning electron microscopy. Unexpectedly, S. epidermidis was the primary isolated bacteria and was also found to be present in all biofilm-positive mucosa specimens, indicating its pivotal role in the pathogenesis of severe chronic infections associated with biofilm formation. We have also measured the activity of myeloperoxidase (MPO), the most abundant neutrophil enzyme, to demonstrate the presence of neutrophils in the samples tested. Our present results show that the level of MPO in CRS associated with biofilm is lower than that without biofilm. It may suggest either a low number of neutrophils or the presence of a type of neutrophils with compromised antimicrobial activity, described as biofilm-associated neutrophils (BAN). Finally, we conclude that further studies with a large number of CRS cases should be performed to establish the association between S. epidermidis and other frequently isolated bacterial species from paranasal sinuses, with the severity of CRS, biofilm formation and the infiltration of BAN.

IL-12 immunotherapy of Braf(V600E)-induced papillary thyroid cancer in a mouse model

Papillary thyroid carcinoma (PTC) accounts for >80% thyroid malignancies, and BRAF(V600E) mutation is frequently found in >40% PTC. Interleukin-12 (IL-12) is a proinflammatory heterodimeric cytokine with strong antitumor activity. It is not known whether IL-12 immunotherapy is effective against Braf(V600E)-induced PTC. In the present study, we investigated the effectiveness of IL-12 immunotherapy against Braf(V600E)-induced PTC in LSL-Braf(V600E)/TPO-Cre mice. LSL-Braf(V600E)/TPO-Cre mice were created for thyroid-specific expression of Braf(V600E) under the endogenous Braf promoter, and spontaneous PTC developed at about 5 weeks of age. The mice were subjected to two treatment regimens: (1) weekly intramuscular injection of 50 μg plasmid DNA expressing a single-chain IL-12 fusion protein (scIL-12/CMVpDNA), (2) daily intraperitoneal injection of mouse recombinant IL-12 protein (mrIL-12, 100 ng per day). The role of T cells, natural killer (NK) cells, and transforming growth factor-β (TGF-β) in IL-12-mediated antitumor effects was determined by a (51)Cr-release cytotoxicity assay. Tumor size and weight were significantly reduced by either weekly intramuscular injection of scIL-12/CMVpDNA or daily intraperitoneal injection of mrIL-12, and tumor became more localized. Survival was significantly increased when treatment started at 1 week of age as compared with that at the 6 weeks of age. Both NK and CD8(+) T cells were involved in the cytotoxicity against tumor cells and their antitumor activity was significantly reduced in tumor-bearing mice. TGF-β also inhibited the antitumor activity of NK and CD8(+) T cells. The immune suppression was completely reversed by IL-12 treatment and partially recovered by anti-TGF-β antibody. We conclude that both IL-12 gene therapy and recombinant protein therapy are effective against PTC. Given that the immune response is significantly suppressed in tumor-bearing mice and can be restored by IL-12, the current study raises a possibility of the application of IL-12 as an adjuvant therapy for thyroid cancer.

Neutrophils in Cancer: Two Sides of the Same Coin

Neutrophils are the most abundant leukocytes in blood and are considered to be the first line of defense during inflammation and infections. In addition, neutrophils are also found infiltrating many types of tumors. Tumor-associated neutrophils (TANs) have relevant roles in malignant disease. Indeed neutrophils may be potent antitumor effector cells. However, increasing clinical evidence shows TANs correlate with poor prognosis. The tumor microenvironment controls neutrophil recruitment and in turn TANs help tumor progression. Hence, TANs can be beneficial or detrimental to the host. It is the purpose of this review to highlight these two sides of the neutrophil coin in cancer and to describe recent studies that provide some light on the mechanisms for neutrophil recruitment to the tumor, for neutrophils supporting tumor progression, and for neutrophil activation to enhance their antitumor functions.