Growth regulated oncogene-alpha expression by murine squamous cell carcinoma promotes tumor growth, metastasis, leukocyte infiltration and angiogenesis by a host CXC receptor-2 dependent mechanism

IL-17A functions and the therapeutic use of IL-17A and IL-17RA targeted antibodies for cancer treatment

Interleukin 17A (IL-17A) is a major member of the IL-17 cytokine family and is produced mainly by T helper 17 (Th17) cells. Other cells such as CD8+ T cells, γδ T cells, natural killer T cells and innate lymphoid-like cells can also produce IL-17A. In healthy individuals, IL-17A has a host-protective capacity, but excessive elevation of IL-17A is associated with the development of autoimmune diseases and cancer. Monoclonal antibodies (mAbs) targeting IL-17A (e.g., ixekizumab and secukinumab) or IL-17A receptor (IL-17RA) (e.g., brodalumab) would be investigated as potential treatments for these diseases. Currently, the application of IL-17A-targeted drugs in autoimmune diseases will provide new ideas for the treatment of tumors, and its combined application with immune checkpoint inhibitors has become a research hotspot. This article reviews the mechanism of action of IL-17A and the application of anti-IL-17A antibodies, focusing on the research progress on the mechanism of action and therapeutic blockade of IL-17A in various tumors such as colorectal cancer (CRC), lung cancer, gastric cancer and breast cancer. Moreover, we also include the results of therapeutic blockade in the field of cancer as well as recent advances in the regulation of IL-17A signaling.

Oncogenic Ras and ΔNp63α cooperate to recruit immunosuppressive polymorphonuclear myeloid-derived suppressor cells in a mouse model of squamous cancer pathogenesis

Introduction

Amplification of human chromosome 3q26-29, which encodes oncoprotein ΔNp63 among other isoforms of the p63 family, is a feature common to squamous cell carcinomas (SCCs) of multiple tissue origins. Along with overexpression of ΔNp63, activation of the protooncogene, RAS, whether by overexpression or oncogenic mutation, is frequently observed in many cancers. In this study, analysis of transcriptome data from The Cancer Genome Atlas (TCGA) demonstrated that expression of TP63 mRNA, particularly ΔNp63 isoforms, and HRAS are significantly elevated in advanced squamous cell carcinomas of the head and neck (HNSCCs), suggesting pathological significance. However, how co-overexpressed ΔNp63 and HRAS affect the immunosuppressive tumor microenvironment (TME) is incompletely understood.

Methods

Here, we established and characterized an immune competent mouse model using primary keratinocytes with retroviral-mediated overexpression of ΔNp63α and constitutively activated HRAS (v-rasHa G12R) to evaluate the role of these oncogenes in the immune TME.

Results

In this model, orthotopic grafting of wildtype syngeneic keratinocytes expressing both v-rasHa and elevated levels of ΔNp63α consistently yield carcinomas in syngeneic hosts, while cells expressing v-rasHa alone yield predominantly papillomas. We found that polymorphonuclear (PMN) myeloid cells, experimentally validated to be immunosuppressive and thus representing myeloid-derived suppressor cells (PMN-MDSCs), were significantly recruited into the TME of carcinomas arising early following orthotopic grafting of ΔNp63α/v-rasHa-expressing keratinocytes. ΔNp63α/v-rasHa-driven carcinomas expressed higher levels of chemokines implicated in recruitment of MDSCs compared to v-rasHa-initiated tumors, providing a heretofore undescribed link between ΔNp63α/HRAS-driven carcinomas and the development of an immunosuppressive TME.

Conclusion

These results support the utilization of a genetic carcinogenesis model harboring specific genomic drivers of malignancy to study mechanisms underlying the development of local immunosuppression.

Targeting oral tumor microenvironment for effective therapy

Oral cancers are among the common head and neck malignancies. Different anticancer therapy modalities such as chemotherapy, immunotherapy, radiation therapy, and also targeted molecular therapy may be prescribed for targeting oral malignancies. Traditionally, it has been assumed that targeting malignant cells alone by anticancer modalities such as chemotherapy and radiotherapy suppresses tumor growth. In the last decade, a large number of experiments have confirmed the pivotal role of other cells and secreted molecules in the tumor microenvironment (TME) on tumor progression. Extracellular matrix and immunosuppressive cells such as tumor-associated macrophages, myeloid-derived suppressor cells (MDSCs), cancer-associated fibroblasts (CAFs), and regulatory T cells (Tregs) play key roles in the progression of tumors like oral cancers and resistance to therapy. On the other hand, infiltrated CD4 + and CD8 + T lymphocytes, and natural killer (NK) cells are key anti-tumor cells that suppress the proliferation of malignant cells. Modulation of extracellular matrix and immunosuppressive cells, and also stimulation of anticancer immunity have been suggested to treat oral malignancies more effectively. Furthermore, the administration of some adjuvants or combination therapy modalities may suppress oral malignancies more effectively. In this review, we discuss various interactions between oral cancer cells and TME. Furthermore, we also review the basic mechanisms within oral TME that may cause resistance to therapy. Potential targets and approaches for overcoming the resistance of oral cancers to various anticancer modalities will also be reviewed. The findings for targeting cells and potential therapeutic targets in clinical studies will also be reviewed.

Curcumin and chemokines: mechanism of action and therapeutic potential in inflammatory diseases

Chemokines belong to the family of cytokines with chemoattractant properties that regulate chemotaxis and leukocyte migration, as well as the induction of angiogenesis and maintenance of hemostasis. Curcumin, the major component of the Curcuma longa rhizome, has various pharmacological actions, including anti-inflammatory, immune-regulatory, anti-oxidative, and lipid-modifying properties. Chemokines and chemokine receptors are influenced/modulated by curcumin. Thus, the current review focuses on the molecular mechanisms associated with curcumin's effects on chemoattractant cytokines, as well as putting into context the many studies that have reported curcumin-mediated regulatory effects on inflammatory conditions in the organs/systems of the body (e.g., the central nervous system, liver, and cardiovascular system). Curcumin's effects on viral and bacterial infections, cancer, and adverse pregnancy outcomes are also reviewed.

The Molecular and Cellular Strategies of Glioblastoma and Non-Small-Cell Lung Cancer Cells Conferring Radioresistance

Ionizing radiation (IR) has been shown to play a crucial role in the treatment of glioblastoma (GBM; grade IV) and non-small-cell lung cancer (NSCLC). Nevertheless, recent studies have indicated that radiotherapy can offer only palliation owing to the radioresistance of GBM and NSCLC. Therefore, delineating the major radioresistance mechanisms may provide novel therapeutic approaches to sensitize these diseases to IR and improve patient outcomes. This review provides insights into the molecular and cellular mechanisms underlying GBM and NSCLC radioresistance, where it sheds light on the role played by cancer stem cells (CSCs), as well as discusses comprehensively how the cellular dormancy/non-proliferating state and polyploidy impact on their survival and relapse post-IR exposure.

Tumor regionalization after surgery: Roles of the tumor microenvironment and neutrophil extracellular traps

Surgery is unanimously regarded as the primary strategy to cure solid tumors in the early stages but is not always used in advanced cases. However, tumor surgery must be carefully considered because the risk of metastasis could be increased by the surgical procedure. Tumor surgery may result in a deep wound, which induces many biological responses favoring tumor metastasis. In particular, NETosis, which is the process of forming neutrophil extracellular traps (NETs), has received attention as a risk factor for surgery-induced metastasis. To reduce cancer mortality, researchers have made efforts to prevent secondary metastasis after resection of the primary tumor. From this point of view, a better understanding of surgery-induced metastasis might provide new strategies for more effective and safer surgical approaches. In this paper, recent insights into the surgical effects on metastasis will be reviewed. Moreover, in-depth opinions about the effects of NETs on metastasis will be discussed.

Therapies that limit the formation of web-like structures formed by white cells known as neutrophils may lower the risk of cancer spread (metastasis) following surgical tumor removal. Removing solid tumors remains a key cancer treatment, but in some cases surgery itself increases the risk of metastasis. Jong-Wan Park at Seoul National University, South Korea, and co-workers reviewed current understanding of metastasis following surgery. Surgical removal destroys the architecture supporting cancer cells but this can release tumor cells into blood vessels. The stress of deep wounds also affects immune responses, most notably neutrophil extracellular traps (NETs), web-like structures formed by neutrophils to trap and kill pathogens. NETs have previously been implicated in metastasis. In a post-surgical environment enriched in neutrophils and pro-inflammatory cytokines, NET formation may help cancer cells thrive, promoting metastasis.

Adipose Tissue Secretion Pattern Influences β-Cell Wellness in the Transition from Obesity to Type 2 Diabetes

The dysregulation of the β-cell functional mass, which is a reduction in the number of β-cells and their ability to secure adequate insulin secretion, represents a key mechanistic factor leading to the onset of type 2 diabetes (T2D). Obesity is recognised as a leading cause of β-cell loss and dysfunction and a risk factor for T2D. The natural history of β-cell failure in obesity-induced T2D can be divided into three steps: (1) β-cell compensatory hyperplasia and insulin hypersecretion, (2) insulin secretory dysfunction, and (3) loss of β-cell mass. Adipose tissue (AT) secretes many hormones/cytokines (adipokines) and fatty acids that can directly influence β-cell function and viability. As this secretory pattern is altered in obese and diabetic patients, it is expected that the cross-talk between AT and pancreatic β-cells could drive the maintenance of the β-cell integrity under physiological conditions and contribute to the reduction in the β-cell functional mass in a dysmetabolic state. In the current review, we summarise the evidence of the ability of the AT secretome to influence each step of β-cell failure, and attempt to draw a timeline of the alterations in the adipokine secretion pattern in the transition from obesity to T2D that reflects the progressive deterioration of the β-cell functional mass.

Chemokine (C-X-C motif) ligand 1/chemokine (C-X-C motif) receptor 2 autocrine loop contributes to cellular proliferation, migration and apoptosis in cervical cancer

Cervical cancer is the most common malignant tumor in gynecology with high mortality rate, so novel approaches for cervical cancer treatment are urgently needed. In this study, we analyzed the gene expression data and clinicopathological data of The Cancer Genome Atlas (TCGA) and Genotype-Tissue Expression Project (GTEx) downloaded from University of California Santa Cruz (UCSC) Xena database. Chemokine (C-X-C motif) ligand 1 (CXCL1) was screened out as a key prognostic gene for cervical cancer. Revealed by the results of ELISA and Western blot, the expression of CXCL1 and chemokine (C-X-C motif) receptor 2 (CXCR2) in cervical cancer cell lines (HeLa and C33A) was significantly higher than that in the primary cervical epithelial cells. Cellular immunofluorescence was used in this study to observe CXCR2 localization. Through CCK8, clone formation assay, wound healing assay and Annexin V/PI staining, it was found that down-regulation of CXCL1 expression or treatment with CXCR2 antagonist (SB 225002) could reduce the cell viability, affect the proliferation, weaken the migration ability, and promote the apoptosis of cervical cancer cells; however, the effect of CXCR2 antagonist was improved after over-expressed CXCL1. CXCL1/CXCR2 chemokine system regulates the proliferation, migration, and apoptosis of cervical cancer cells in the form of an autocrine loop, thus affecting the development of cervical cancer. This study provides a theoretical basis for researching the molecular mechanism of cervical cancer deterioration and development, and brings forward a new idea for the prevention and treatment of cervical cancer.

A low direct electrical signal attenuates oxidative stress and inflammation in septic rats

Electrical stimulation is proposed to exert an antimicrobial effect according to studies performed using bacterial and cell cultures. Therefore, we investigated the effects of electrification on inflammation in septic rats. Twenty-eight male Wistar albino rats were divided into 4 groups: healthy control (C), electrified healthy (E), sepsis (S), and electrified sepsis (SE) groups. Staphylococcus aureus (1 x 109 colonies) in 1 ml of medium was intraperitoneally injected into rats to produce a sepsis model. The rats in the E and SE groups were exposed to a low direct electrical signal (300 Hz and 2.5 volts) for 40 min and 1 and 6 h after bacterial infection. Immediately after the second electrical signal application, blood and tissue samples of the heart, lung, and liver were collected. An antibacterial effect of a low direct electrical signal was observed in the blood of rats. The effects of electrical signals on ameliorating changes in the histological structure of tissues, blood pH, gases, viscosity and cell count, activities of some important enzymes, oxidative stress parameters, inflammation and tissue apoptosis were observed in the SE group compared to the S group. Low direct electrical signal application exerts antibacterial, antioxidant, anti-inflammatory and antiapoptotic effects on septic rats due to the induction of electrolysis in body fluids without producing any tissue damage.

Sirolimus diminishes the expression of GRO-α (CXCL-1) /CXCR2 axis in human keratinocytes and cutaneous squamous cell carcinoma cells

BACKGROUND

Organ transplant recipients show a high incidence for the formation of cutaneous squamous cell carcinoma (cSCC), while sirolimus appears to reduce the risk. GRO-α is a chemokine, which is overexpressed in many tumor entities and associated with malignant transformation. However, little is known about the expression and function of GRO-α in human cSCC.

OBJECTIVE

Our aim was to investigate the relevance of the GRO-α (CXCL-1)/ CXCR2 axis in human cSCC and the potential impact of sirolimus.

METHODS

We analyzed the GRO-α expression in human keratinocytes, different cSCC cell lines as well as cSCC tissue and investigated its effect on cell proliferation and migration. Additionally, we incubated cells with sirolimus and measured the expression of GRO-α and its receptor CXCR2.

RESULTS

We showed that both constitutive as well as induced GRO-α expression is higher in in cSCC cell lines compared to keratinocytes and that GRO-α protein is detectable in human cSCC tissue. By GRO-α exposure and shRNA knock down, we identified GRO-α as a driving factor in proliferation and migration. Moreover, in a dermis equivalent GRO-α knocked down cSCC cell lines displayed a reduced capacity in tumor nest formation. Incubation with sirolimus significantly inhibited GRO-α expression in keratinocytes as well as tumor cell lines. Moreover, sirolimus decreased the expression of the corresponding receptor CXCR2.

CONCLUSION

Taken together, our results suggest that the GRO-α/CXCR2 axis plays a role in human keratinocyte carcinogenesis and might represent a molecular mechanism for the preventive effect of mTOR inhibitors in cSCC development.

Lipopolysaccharide-Mediated Chronic Inflammation Promotes Tobacco Carcinogen-Induced Lung Cancer and Determines the Efficacy of Immunotherapy

Chronic obstructive pulmonary disease (COPD) is an inflammatory disease that is associated with increased risk of lung cancer. Pseudomonas aeruginosa (PA) infections are frequent in patients with COPD, which increase lung inflammation and acute exacerbations. However, the influences of PA-induced inflammation on lung tumorigenesis and the efficacy of immune checkpoint blockade remain unknown. In this study, we initiated a murine model of lung cancer by treating FVB/NJ female mice with tobacco carcinogen nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) alone or in combination with PA-lipopolysaccharide (LPS). LPS-mediated chronic inflammation induced T-cell exhaustion, increased the programmed cell death-1 (PD-1)/programmed cell death ligand-1 (PD-L1) axis, and enhanced NNK-induced lung tumorigenesis through an immunosuppressive microenvironment characterized by accumulation of myeloid-derived suppressive cells (MDSC) and regulatory T cells. Anti-PD-1 antibody treatment reduced tumors in NNK/LPS-treated mice with a 10-week LPS treatment but failed to inhibit tumor growth when LPS exposure was prolonged to 16 weeks. Anti-Ly6G antibody treatment coupled with depletion of MDSC alone reduced tumor growth; when combined with anti-PD-1 antibody, this treatment further enhanced antitumor activity in 16-week NNK/LPS-treated mice. Immune gene signatures from a human lung cancer dataset of PD-1 blockade were identified, which predicted treatment responses and survival outcome and overlapped with those from the mouse model. This study demonstrated that LPS-mediated chronic inflammation creates a favorable immunosuppressive microenvironment for tumor progression and correlates with the efficacy of anti-PD-1 treatment in mice. Immune gene signatures overlap with human and mouse lung tumors, providing potentially predictive markers for patients undergoing immunotherapy. SIGNIFICANCE: This study identifies an immune gene signature that predicts treatment responses and survival in patients with tobacco carcinogen-induced lung cancer receiving immune checkpoint blockade therapy.

Ovarian Cancer: Therapeutic Strategies to Overcome Immune Suppression

Ovarian cancer generally escapes diagnosis until the advanced stages. High-grade serous ovarian cancer (HGSOC) is the most frequently occurring form of this malaise and is a disease which has the highest mortality rate of gynecologic cancers. Over recent years it has been revealed that the course of such cancers can be significantly influenced by the nature of immune cells in tumors at the time of diagnosis and by immune cells induced by therapy. Numerous investigators have since focused on disease biology to identify biomarkers or therapeutic targets. Yet, while over the past decade there have been significant improvements in state-of-the-art surgery for ovarian cancer as frontline therapy, there have been limited advancements in the development of novel curative or management drugs for this disease. This chapter discusses the major elements of immune suppression in HGSOC from a biological viewpoint, mechanisms of overcoming resistance to therapies, and recent therapy aimed at improving patient care and survival.

MAGE-A3 is a prognostic biomarker for poor clinical outcome in cutaneous squamous cell carcinoma with perineural invasion via modulation of cell proliferation

Perineural invasion is a pathologic process of neoplastic dissemination along and invading into the nerves. Perineural invasion is associated with aggressive disease and a greater likelihood of poor outcomes. In this study, 3 of 9 patients with cutaneous squamous cell carcinoma and perineural invasion exhibited poor clinical outcomes. Tumors from these patients expressed high levels of MAGE-A3, a cancer testis antigen that may contribute to key processes of tumor development. In addition to perineural invasion, the tumors exhibited poor differentiation and deep invasion and were subsequently classified as Brigham and Women's Hospital tumor stage 3. Cyclin E, A and B mRNA levels were increased in these tumors compared with normal skin tissues (102.93±15.03 vs. 27.15±4.59, 36.83±19.41 vs. 11.59±5.83, 343.77±86.49 vs. 95.65±29.25, respectively; p<0.05). A431 cutaneous squamous cell carcinoma cells pretreated with MAGE-A3 antibody exhibited a decreased percentage S-phase cells (14.13±2.8% vs. 33.97±1.1%; p<0.05) and reduced closure in scratch assays (43.88±5.49% vs. 61.17±3.97%; p = 0.0058). In a syngeneic animal model of squamous cell carcinoma, immunoblots revealed overexpression of MAGE-A3 and cyclin E, A, and B protein in tumors at 6 weeks. However, knockout of MAGE-A3 expression caused a reduction in tumor growth (mean tumor volume 155.3 mm3 vs. 3.2 mm3) compared with parental cells. These results suggest that MAGE-A3 is a key mediator in cancer progression. Moreover, elevated collagen XI and matrix metalloproteases 3, 10, 11, and 13 mRNA levels were observed in poorly differentiated cutaneous squamous cell carcinoma with perineural invasion compared with normal skin tissue (1132.56±882.7 vs. 107.62±183.62, 1118.15±1109.49 vs. 9.5±5, 2603.87±2385.26 vs. 5.29±3, 957.95±627.14 vs. 400.42±967.66, 1149.13±832.18 vs. 19.41±35.62, respectively; p<0.05). In summary, this study highlights the potential prognostic value of MAGE-A3 in clinical outcomes of cutaneous squamous cell carcinoma patients.

Tumor Associated Neutrophils. Their Role in Tumorigenesis, Metastasis, Prognosis and Therapy

Tumor Associated Neutrophils (TANs) are engaged into the tumor microenvironment by cytokines and chemokines, can be distinguished according to their activation and cytokine status and effects on tumor cell growing in N1 and N2 TANs. N1 TANs exert an antitumor activity, by direct or indirect cytotoxicity. N2 TANs stimulate immunosuppression, tumor growth, angiogenesis and metastasis by DNA instability, or by cytokines and chemokines release. In tumor patients, either a high number of TANs and Neutrophil-to-Lymphocyte Ratio (NLR) do correlate with poor prognosis, and, so far, TAN counts and NLR can be regarded as biomarkers. Owing to the pivotal role of TANs in stimulating tumor progression, therapeutic strategies to target TANs have been suggested, and two major approaches have been proposed: (a) targeting the CXCL-8/CXCR-1/CXCR-2 axis, thereby blocking TANs or (b) targeting substances produced by polymorpho-nuclear cells that promote tumor growth. Many studies have been accomplished either in vitro and in animal models, whereas clinical studies are restrained, presently, due to the risk of inducing immunosuppression. In this review, we deeply discuss the anti-tumorigenic or pro-tumorigenic activity of TANs. In particular, TANs relevance in tumor prognosis and in vitro therapeutic strategies are widely described. On-going clinical trials, aimed to inhibit neutrophil recruitment into the tumor are also accurately debated.

Strategies to Improve Cancer Immune Checkpoint Inhibitors Efficacy, Other Than Abscopal Effect: A Systematic Review

Despite that the impact of immune checkpoint inhibitors on malignancies treatment is unprecedented, a lack of response to these molecules is observed in several cases. Differently from melanoma and non-small cell lung cancer, where the use of immune checkpoint inhibitors results in a high efficacy, the response rate in other tumors, such as gastrointestinal cancers, breast cancer, sarcomas, and part of genitourinary cancers remains low. The first strategy evaluated to improve the response rate to immune checkpoint inhibitors is the use of predictive factors for the response such as PD-L1 expression, tumor mutational burden, and clinical features. In addition to the identification of the patients with a higher expression of immune checkpoint molecules, another approach currently under intensive investigation is the use of therapeutics in a combinatory manner with immune checkpoint inhibitors in order to obtain an enhancement of efficacy through the modification of the tumor immune microenvironment. In addition to the abscopal effect induced by radiotherapy, a lot of studies are evaluating several drugs able to improve the response rate to immune checkpoint inhibitors, including microbiota modifiers, drugs targeting co-inhibitory receptors, anti-angiogenic therapeutics, small molecules, and oncolytic viruses. In view of the rapid and extensive development of this research field, we conducted a systematic review of the literature identifying which of these drugs are closer to achieving validation in the clinical practice.

Inhibiting myeloid-derived suppressor cell trafficking enhances T cell immunotherapy

Recruitment of myeloid-derived suppressor cells (MDSCs) into tumors induces local immunosuppression in carcinomas. Here, we assessed whether SX-682, an orally bioavailable small-molecule inhibitor of CXCR1 and CXCR2, could block tumor MDSC recruitment and enhance T cell activation and antitumor immunity following multiple forms of immunotherapy. CXCR2+ neutrophilic MDSCs (PMN-MDSCs) were the most abundant myeloid cell subset within oral and lung syngeneic carcinomas. PMN-MDSCs demonstrated greater suppression of tumor-infiltrating lymphocyte killing of targets compared with macrophages. SX-682 significantly inhibited trafficking of PMN-MDSCs without altering CXCR2 ligand expression. Trafficking of CXCR1+ macrophages was unaltered, possibly due to coexpression of CSF1R. Reduced PMN-MDSC tumor infiltration correlated with enhanced accumulation of endogenous or adoptively transferred T cells. Accordingly, tumor growth inhibition or the rate of established tumor rejection following programed death-axis (PD-axis) immune checkpoint blockade or adoptive cell transfer of engineered T cells was enhanced in combination with SX-682. Despite CXCR1/2 expression on tumor cells, SX-682 appeared to have little direct antitumor effect on these carcinoma models. These data suggest that tumor-infiltrating CXCR2+ PMN-MDSCs may prevent optimal responses following both PD-axis immune checkpoint blockade and adoptive T cell transfer therapy. Abrogation of PMN-MDSC trafficking with SX-682 enhances T cell-based immunotherapeutic efficacy and may be of benefit to patients with MDSC-infiltrated cancers.

Semaphorin4D Inhibition Improves Response to Immune-Checkpoint Blockade via Attenuation of MDSC Recruitment and Function

Tumor infiltration by immunosuppressive myeloid cells, such as myeloid-derived suppressor cells (MDSCs), causes resistance to immunotherapy. Semaphorin4D, originally characterized for its axonal guidance properties, also contributes to endothelial cell migration and survival and modulates global immune cytokine profiles and myeloid cell polarization within the tumor microenvironment. Here, we show how a therapeutic murine Sema4D mAb improves responses to immune-checkpoint blockade (ICB) in two murine carcinoma models. Treatment of tumor-bearing mice with Sema4D mAb abrogated Ly6G^hi PMN-MDSC recruitment through reducing MAPK-dependent chemokine production by tumor cells in Murine oral cancer-1 (MOC1) tumors. PMN-MDSC suppressive capacity was reduced through inhibition of Sema4D-driven arginase expression. These changes led to enhanced tumor infiltration by CD8⁺ TIL and activation of tumor-draining lymph node T lymphocytes in response to tumor antigen. Sema4D mAb in combination with either CTLA-4 or PD-1 blockade enhanced rejection of tumors or tumor growth delay, resulting in prolonged survival with either treatment. This function of Sema4D mAb provides a rationale for its evaluation in combination with ICB to treat tumors with immunosuppressive myeloid infiltration.

Regulation of Ovarian Cancer Prognosis by Immune Cells in the Tumor Microenvironment

It is estimated that in the United States in 2018 there will be 22,240 new cases of ovarian cancer and 14,070 deaths due to this malignancy. The most common subgroup of this disease is high-grade serous ovarian cancer (HGSOC), which is known for its aggressiveness, high recurrence rate, metastasis to other sites, and the development of resistance to conventional therapy. It is important to understand the ovarian cancer tumor microenvironment (TME) from the viewpoint of the function of pre-existing immune cells, as immunocompetent cells are crucial to mounting robust antitumor responses to prevent visible tumor lesions, disease progression, or recurrence. Networks consisting of innate and adaptive immune cells, metabolic pathways, intracellular signaling molecules, and a vast array of soluble factors, shape the pathogenic nature of the TME and are useful prognostic indicators of responses to conventional therapy and immunotherapy, and subsequent survival rates. This review highlights key immune cells and soluble molecules in the TME of ovarian cancer, which are important in the development of effective antitumor immunity, as well as those that impair effector T cell activity. A more insightful knowledge of the HGSOC TME will reveal potential immune biomarkers to aid in the early detection of this disease, as well as biomarkers that may be targeted to advance the design of novel therapies that induce potent antitumor immunity and survival benefit.

Regulation of Ovarian Cancer Prognosis by Immune Cells in the Tumor Microenvironment

It is estimated that in the United States in 2018 there will be 22,240 new cases of ovarian cancer and 14,070 deaths due to this malignancy. The most common subgroup of this disease is high-grade serous ovarian cancer (HGSOC), which is known for its aggressiveness, high recurrence rate, metastasis to other sites, and the development of resistance to conventional therapy. It is important to understand the ovarian cancer tumor microenvironment (TME) from the viewpoint of the function of pre-existing immune cells, as immunocompetent cells are crucial to mounting robust antitumor responses to prevent visible tumor lesions, disease progression, or recurrence. Networks consisting of innate and adaptive immune cells, metabolic pathways, intracellular signaling molecules, and a vast array of soluble factors, shape the pathogenic nature of the TME and are useful prognostic indicators of responses to conventional therapy and immunotherapy, and subsequent survival rates. This review highlights key immune cells and soluble molecules in the TME of ovarian cancer, which are important in the development of effective antitumor immunity, as well as those that impair effector T cell activity. A more insightful knowledge of the HGSOC TME will reveal potential immune biomarkers to aid in the early detection of this disease, as well as biomarkers that may be targeted to advance the design of novel therapies that induce potent antitumor immunity and survival benefit.

Regulation of Ovarian Cancer Prognosis by Immune Cells in the Tumor Microenvironment

It is estimated that in the United States in 2018 there will be 22,240 new cases of ovarian cancer and 14,070 deaths due to this malignancy. The most common subgroup of this disease is high-grade serous ovarian cancer (HGSOC), which is known for its aggressiveness, high recurrence rate, metastasis to other sites, and the development of resistance to conventional therapy. It is important to understand the ovarian cancer tumor microenvironment (TME) from the viewpoint of the function of pre-existing immune cells, as immunocompetent cells are crucial to mounting robust antitumor responses to prevent visible tumor lesions, disease progression, or recurrence. Networks consisting of innate and adaptive immune cells, metabolic pathways, intracellular signaling molecules, and a vast array of soluble factors, shape the pathogenic nature of the TME and are useful prognostic indicators of responses to conventional therapy and immunotherapy, and subsequent survival rates. This review highlights key immune cells and soluble molecules in the TME of ovarian cancer, which are important in the development of effective antitumor immunity, as well as those that impair effector T cell activity. A more insightful knowledge of the HGSOC TME will reveal potential immune biomarkers to aid in the early detection of this disease, as well as biomarkers that may be targeted to advance the design of novel therapies that induce potent antitumor immunity and survival benefit.

The Role of Curcumin in Prevention and Management of Metastatic Disease

In the last two decades, targeted therapies have enhanced tumor patient care and treatment success, however, metastatic growth still cannot be stopped efficiently and, therefore, mortality rates remain high. Prevention strategies against formation of metastases are the most promising approach we have, however, due to lack of clinical validation studies, they have not yet entered routine clinical care. In order to smooth the way for efficient prevention, further preclinical and large clinical studies are required. In this context, the underlying molecular mechanisms and factors that lead to metastatic growth have to be explored, and potential preventive agents have to be tested. Thereby, special attention has to be paid to natural bioactive compounds which do not exert major adverse effects, like the plant-derived polyphenol Curcumin, which is known to be a powerful antitumor agent. So far, most of the preclinical studies with Curcumin have focused on its effect on inhibiting tumor cell proliferation and invasion, although, it is known that it also inhibits metastatic spread in vivo. This review discusses the preventive potential of this natural compound not only against tumor onset, but also against formation of metastases.

GRO-α and IL-8 enhance ovarian cancer metastatic potential via the CXCR2-mediated TAK1/NFκB signaling cascade

Intraperitoneal metastasis is a common occurrence and is usually involved in the poor prognosis of ovarian cancer. Its specific metastatic pattern implies that certain indispensable microenvironmental factors secreted in the peritoneal cavity can direct metastatic ovarian cancer cells to permissive niches for secondary lesion formation. However, the underlying molecular mechanisms are ill defined. Herein, we report that GRO-α and IL-8 are predominately upregulated in culture media derived from either normal or cancerous omenta and are associated with increased ovarian cancer aggressiveness. Methods: OCM was established from culture medium of fresh human omental tissues. Primary and metastatic ovarian cancer cell lines were generated from human tumor tissues and verified by specific antibodies. The functional roles of GRO-α, IL-8, and their specific receptor CXCR2 were examined by neutralizing antibodies, shRNA gene knockdown, CRISPR/Cas9 gene knockout and pharmaceutical CXCR2 inhibitor SB225002. The oncogenic properties of ovarian cancer cells were examined by in vitro and in vivo mouse models. Results: Both GRO-α and IL-8 can activate TAK1/NFκB signaling via the CXCR2 receptor. Intriguingly, TAK1/NFκB signaling activity was higher in metastatic ovarian cancer cells; this higher activity makes them more susceptible to OCM-induced tumor aggressiveness. Treatment of ovarian cancer cells with GRO-α and IL-8 neutralizing antibodies or ablation of CXCR2 by shRNA gene knockdown, CRISPR/Cas9 gene knockout, or CXCR2 inhibitor SB225002 treatment significantly attenuated TAK1/NFκB signaling and decreased in vitro and in vivo oncogenic and metastatic potential, suggesting CXCR2 plays a key role in the GRO-α and IL-8-governed metastatic spreading of ovarian cancer cells in the intraperitoneal cavity. Conclusion: This study highlights the significance of GRO-α and IL-8 as the key chemokines in the peritoneal tumor microenvironment and suggests the utility of targeting their receptor CXCR2 as a potential target-based therapy for peritoneal metastases of ovarian cancer.

Thrombocytosis as a prognostic factor in inflammatory breast cancer

PURPOSE

Platelets are essential components of hemostasis and also play an important role in the tumor microenvironment. The purposes of our research were to examine the role of thrombocytosis in inflammatory breast cancer (IBC) and to know which cytokine drives thrombocytosis.

METHODS

We reviewed the medical records of 3654 patients with stage I-III breast cancer treated between 1998 and 2013, including 230 patients (6%) with IBC. We used Chi-squared test or Fisher's exact test to compare the variables between patients with and without thrombocytosis. Multivariate Cox regression models were used to determine the association of thrombocytosis with overall survival. We also examined baseline serum cytokine levels in 81 patients with primary IBC to determine the association of inflammatory cytokines with thrombocytosis.

RESULTS

We found that thrombocytosis was the only variable that predicted prognosis. Fifty-five patients (1.5%) had thrombocytosis. Thrombocytosis was more prevalent in patients with IBC than in those with non-IBC (3.4% vs. 1.4%, p = 0.015). In patients with IBC, thrombocytosis was associated with worse overall survival [hazard ratio 2.38, 95% confidence interval (CI) 1.05-5.4, p = 0.0378]. Circulating levels of growth-regulated oncogene (GRO) (odds ratio 1.003, 95% CI 1.001-1.005, p = 0.0019) and transforming growth factor β (TGF-β) (odds ratio 1.3, 95% CI 1.128-1.499, p = 0.0003) were associated with thrombocytosis.

CONCLUSIONS

Thrombocytosis was more prevalent in patients with IBC than in those with non-IBC and it was associated with poor prognosis. GRO and TGF-β were associated with thrombocytosis in IBC.

The prognostic implications of growth-related gene product β in laryngeal squamous cell carcinoma

Growth-related gene product β (GROβ) is an angiogenic chemokine that belongs to the CXC chemokine family, and a number of studies have suggested that GROβ is associated with tumor development and progression. However, a number of studies have investigated the association between GROβ expression and the clinical attributes of laryngeal squamous cell carcinoma (LSCC). In the present study, one-step quantitative polymerase chain reaction and immunohistochemistry analysis were used to detect GROβ expression and evaluate the association between its expression and the clinicopathological characteristics of LSCC. The results demonstrated that the GROβ mRNA and protein expression levels were significantly increased in LSCC compared with the corresponding non-cancerous tissues. GROβ protein expression in LSCC was associated with tumor-node-metastasis stage, lymph node metastasis and histopathological grade. The Kaplan-Meier method and Cox multi-factor analysis indicated that high GROβ expression, lymph node metastasis and histopathological grade were significantly associated with poor survival of patients with LSCC. These data indicated that GROβ may be a novel prognostic biomarker of LSCC.

RNA-seq Reveals Transcriptomic Differences in Inflamed and Noninflamed Intestinal Mucosa of Crohn's Disease Patients Compared with Normal Mucosa of Healthy Controls

BACKGROUND

Aberrant gene expression in the gut mucosa might contribute to the initiation and progression of Crohn's disease (CD). RNA sequencing (RNA-seq) provides precise measurements of expression levels of transcripts and their isoforms. The aim of this study was to use RNA-seq to investigate transcriptomic differences and identify significantly differentially expressed transcripts in inflamed and noninflamed intestinal mucosa of CD patients.

METHODS

RNA-seq was performed on 13 pairs of inflamed and noninflamed intestinal mucosa from 13 CD patients and on sex-matched normal mucosa of 13 healthy controls. Significantly differentially expressed transcripts were validated by immunohistochemistry, quantitative reverse transcriptase polymerase chain reaction, and enzyme-linked immunosorbent assay.

RESULTS

RNA-seq revealed genome-wide transcriptomic differences between normal mucosa, noninflamed, and inflamed CD mucosa. Among 950 differentially expressed genes, 19 were up- or downregulated (upregulation: ANGPT2, CHN1, CPXM1, CPZ, CXCL1, FCN3, GJC1, HSD11B1, LZTS1, MEOX1, MMP12, PLA1A, SERPINE1, SGIP1, and TRPC4; downregulation: FAM189A1, PDE6A, SLC38A4, and HMGCS2) with statistical significance (p < 0.01 and q < 0.05). Among them, CXCL1 exhibited the highest fold change between groups. Immunohistochemistry for CXCL1 revealed no expression in normal mucosa, slightly increased expression in noninflamed CD mucosa, and highly increased expression in inflamed CD mucosa. Quantitative reverse transcriptase polymerase chain reaction showed that CXCL1 expression was significantly associated with epithelial damage, increased infiltration of polymorphonuclear leukocytes, and submucosal fibrosis. Serum CXCL1 concentration measured by enzyme-linked immunosorbent assay was better correlated with CD activity index (r = 0.660) than with C-reactive protein (r = 0.204).

CONCLUSIONS

RNA-seq revealed transcriptomic differences between normal mucosa, noninflamed CD mucosa, and inflamed CD mucosa. Intestinal and serum CXCL1 was substantially increased with CD activity and can be used as a potential biomarker of CD.

Resistance to CTLA-4 checkpoint inhibition reversed through selective elimination of granulocytic myeloid cells

Purpose

Local immunosuppression remains a critical problem that limits clinically meaningful response to checkpoint inhibition in patients with head and neck cancer. Here, we assessed the impact of MDSC elimination on responses to CTLA-4 checkpoint inhibition.

Experimental Design

Murine syngeneic carcinoma immune infiltrates were characterized by flow cytometry. Granulocytic MDSCs (gMDSCs) were depleted and T-lymphocyte antigen-specific responses were measured. Tumor-bearing mice were treated with MDSC depletion and CTLA-4 checkpoint blockade. Immune signatures within the human HNSCC datasets from The Cancer Genome Atlas (TCGA) were analyzed and differentially expressed genes from sorted human peripheral MDSCs were examined.

Results

gMDSCs accumulated with tumor progression and correlated with depletion of effector immune cells. Selective depletion of gMDSC restored tumor and draining lymph node antigen-specific T-lymphocyte responses lost with tumor progression. A subset of T-cell inflamed tumors responded to CTLA-4 mAb alone, but the addition of gMDSC depletion induced CD8 T-lymphocyte-dependent rejection of established tumors in all treated mice that resulted in immunologic memory. MDSCs differentially expressed chemokine receptors. Analysis of the head and neck cancer TCGA cohort revealed high CTLA-4 and MDSC-related chemokine and an MDSC-rich gene expression profile with a T-cell inflamed phenotype in > 60% of patients. CXCR2 and CSF1R expression was validated on sorted peripheral blood MDSCs from HNSCC patients.

Conclusions

MDSCs are a major contributor to local immunosuppression that limits responses to checkpoint inhibition in head and neck cancer. Limitation of MDSC recruitment or function represents a rational strategy to enhance responses to CTLA-4-based checkpoint inhibition in these patients.

Anti-PD-L1 Efficacy Can Be Enhanced by Inhibition of Myeloid-Derived Suppressor Cells with a Selective Inhibitor of PI3Kδ/γ

Checkpoint inhibitors are relatively inefficacious in head and neck cancers, despite an abundance of genetic alterations and a T-cell-inflamed phenotype. One significant barrier to efficacy may be the recruitment of myeloid-derived suppressor cells (MDSC) into the tumor microenvironment. Here we demonstrate functional inhibition of MDSC with IPI-145, an inhibitor of PI3Kδ and PI3Kγ isoforms, which enhances responses to PD-L1 blockade. Combination therapy induced CD8⁺ T lymphocyte-dependent primary tumor growth delay and prolonged survival only in T-cell-inflamed tumor models of head and neck cancers. However, higher doses of IPI-145 reversed the observed enhancement of anti-PD-L1 efficacy due to off-target suppression of the activity of tumor-infiltrating T lymphocytes. Together, our results offer a preclinical proof of concept for the low-dose use of isoform-specific PI3Kδ/γ inhibitors to suppress MDSC to enhance responses to immune checkpoint blockade. Cancer Res; 77(10); 2607-19. ©2017 AACR.

Overcoming barriers to effective immunotherapy: MDSCs, TAMs, and Tregs as mediators of the immunosuppressive microenvironment in head and neck cancer

A significant subset of head and neck cancers display a T-cell inflamed phenotype, suggesting that patients with these tumors should respond to therapeutic approaches aimed at strengthening anti-tumor immune responses. A major barrier to the development of an effective anti-tumor immune response, at baseline or in response to immunotherapy, is the development of an immunosuppressive tumor microenvironment. Several well described mechanisms of effector immune cell suppression in the head and neck cancer microenvironment are discussed here, along with updates on current trials designed to translate what we have learned from pre-clinical and correlative clinical studies into improved responses in patients with head and neck cancer following immune activating therapies.

Enhanced Tumor Control with Combination mTOR and PD-L1 Inhibition in Syngeneic Oral Cavity Cancers

Significant subsets of patients with oral cancer fail to respond to single-agent programmed death (PD) blockade. Syngeneic models of oral cancer were used to determine if blocking oncogenic signaling improved in vivo responses to PD-L1 monoclonal antibody (mAb). Anti-PD-L1 enhanced durable primary tumor control and survival when combined with mTOR (rapamycin), but not in combination with MEK inhibition (PD901) in immunogenic MOC1 tumors. Conversely, PD-L1 mAb did not enhance tumor control in poorly immunogenic MOC2 tumors. Rapamycin enhanced expansion of peripheral antigen-specific CD8 T cells and IFNγ production following ex vivo antigen stimulation. More CD8 T cells infiltrated and were activated after PD-L1 mAb treatment in mice with immunogenic MOC1 tumors, which were stable or increased by the addition of rapamycin, but suppressed when PD901 was added. Rapamycin increased IFNγ production capacity in peripheral and tumor-infiltrating CD8 T cells. In vivo antibody depletion revealed a CD8 T-cell-dependent, and not NK cell-dependent mechanism of tumor growth inhibition after treatment with rapamycin and PD-L1 mAb, ruling out significant effects from NK cell-mediated antibody-dependent cellular cytotoxicity. Rapamycin also enhanced IFNγ or PD-L1 mAb treatment-associated induction of MHC class I expression on MOC1 tumor cells, an effect abrogated by depleting infiltrating CD8 T cells from the tumor microenvironment. These data conflict with traditional views of rapamycin as a universal immunosuppressant, and when combined with evidence of enhanced antitumor activity with the combination of rapamycin and PD-L1 mAb, suggest that this treatment combination deserves careful evaluation in the clinical setting. Cancer Immunol Res; 4(7); 611-20. ©2016 AACR.

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.

Anti-Tumor Immunity in Head and Neck Cancer: Understanding the Evidence, How Tumors Escape and Immunotherapeutic Approaches

Many carcinogen- and human papilloma virus (HPV)-associated head and neck cancers (HNSCC) display a hematopoietic cell infiltrate indicative of a T-cell inflamed phenotype and an underlying anti-tumor immune response. However, by definition, these tumors have escaped immune elimination and formed a clinically significant malignancy. A number of both genetic and environmental mechanisms may allow such immune escape, including selection of poorly antigenic cancer cell subsets, tumor produced proinflammatory and immunosuppressive cytokines, recruitment of immunosuppressive immune cell subsets into the tumor and expression of checkpoint pathway components that limit T-cell responses. Here, we explore concepts of antigenicity and immunogenicity in solid tumors, summarize the scientific and clinical data that supports the use of immunotherapeutic approaches in patients with head and neck cancer, and discuss immune-based treatment approaches currently in clinical trials.

CXCL1 expression is correlated with Snail expression and affects the prognosis of patients with gastric cancer

Gastric cancer (GC) continues to result in a poor survival rate and prognostic biomarkers for the disease are lacking. Chemokine (C-X-C motif) ligand (CXCL1) expression plays a critical role in tumor metastasis, and Snail promotes epithelial-mesenchymal transition (EMT) to promote metastasis. Therefore, the present study aimed to investigate the correlation between CXCL1 and Snail expression and the effect of CXCL1 expression on the survival of patients with GC. CXCL1 and Snail expression in paraffin-embedded tissue sections from 127 patients with GC were each assessed by immunohistochemistry. Cox regression and Kaplan-Meier analyses were performed to evaluate the prognostic significance of CXCL1 and Snail. Evaluation of the association between CXCL1 and Snail expression and clinical characteristics was based on the χ² test. Spearman's rank correlation coefficient and Fisher's exact test were used to explore the association between CXCL1 and Snail expression in GC tissues. CXCL1 was found to be significantly associated with tumor invasion (P=0.003), tumor-node-metastasis (TNM) staging (P=0.001), tumor size (P=0.013) and lymph node metastasis (P=0.022) in GC. Snail overexpression was also significantly associated with tumor invasion (P=0.001), TNM staging (P=0.005), tumor size (P=0.026), lymph node metastases (P=0.014) and perineural invasion (P=0.009). CXCL1 and Snail expression were independent factors for a worse overall survival rate, as determined by multivariate analysis (P=0.011 and P=0.018; respectively). The combined expression of CXCL1 and Snail resulted in a worse prognosis compared with the other three groups (P=0.005). Furthermore, there was a significantly positive correlation between CXCL1 and Snail expression in GC (r=0.431; P<0.001). The expression of CXCL1 is significantly associated with Snail expression and may be used as a predictive co-biomarker for patient prognosis and tumor aggressiveness in GC. CXCL1 may promote GC metastasis by regulating EMT.

Vinyl sulfone analogs of lysophosphatidylcholine irreversibly inhibit autotaxin and prevent angiogenesis in melanoma

Autotaxin (ATX) is an enzyme discovered in the conditioned medium of cultured melanoma cells and identified as a protein that strongly stimulates motility. This unique ectonucleotide pyrophosphatase and phosphodiesterase facilitates the removal of a choline headgroup from lysophosphatidylcholine (LPC) to yield lysophosphatidic acid (LPA), which is a potent lipid stimulator of tumorigenesis. Thus, ATX has received renewed attention because it has a prominent role in malignant progression with significant translational potential. Specifically, we sought to develop active site-targeted irreversible inhibitors as anti-cancer agents. Herein we describe the synthesis and biological activity of an LPC-mimetic electrophilic affinity label that targets the active site of ATX, which has a critical threonine residue that acts as a nucleophile in the lysophospholipase D reaction to liberate choline. We synthesized a set of quaternary ammonium derivative-containing vinyl sulfone analogs of LPC that function as irreversible inhibitors of ATX and inactivate the enzyme. The analogs were tested in cell viability assays using multiple cancer cell lines. The IC50 values ranged from 6.74 to 0.39 μM, consistent with a Ki of 3.50 μM for inhibition of ATX by the C16H33 vinyl sulfone analog CVS-16 (10b). A phenyl vinyl sulfone control compound, PVS-16, lacking the choline-like quaternary ammonium mimicking head group moiety, had little effect on cell viability and did not inhibit ATX. Most importantly, CVS-16 (10b) significantly inhibited melanoma progression in an in vivo tumor model by preventing angiogenesis. Taken together, this suggests that CVS-16 (10b) is a potent and irreversible ATX inhibitor with significant biological activity both in vitro and in vivo.

Inflammatory serum proteins are severely altered in metastatic gastric adenocarcinoma patients from the Chinese population

BACKGROUND

Inflammation is one of the major hallmarks of cancer. This study was designed to profile a panel of inflammatory mediators in gastric adenocarcinoma (GA) and to identify their potential differences separately in metastatic and non-metastatic patient subgroups.

METHODS

Serum samples from 216 GA patients and 333 healthy controls from China were analyzed for six proteins using the Luminex multiplex assay.

RESULTS

The serum levels for all the six proteins were significantly elevated in metastatic GA compared to non-metastatic GA. Two acute phase proteins (SAA and CRP) and a CXC chemokine (GRO) were significantly elevated in metastatic GA (p <0.01) but smaller changes were observed in non-metastatic GA compared to healthy controls. OPN is moderately increased in non-metastatic GA (2.05-fold) and more severely elevated in metastatic GA (3.34-fold). Surprisingly, soluble VCAM1 and AGP were significantly lower in both non-metastatic and metastatic GA patients compared to controls. Several individual proteins were shown to possess moderate diagnostic value for non-metastatic GA (AUC = 0.786, 0.833, 0.823 for OPN, sVCAM1 and AGP, respectively) and metastatic GA (AUC = 0.931, 0.720, 0.834 and 0.737 for OPN, sVCAM1, SAA and CRP, respectively). However, protein combinations further improve the diagnostic potential for both non-metastatic GA (best AUC = 0.946) and metastatic GA (best AUC = 0.963). The protein combination with best AUC value for both comparisons is OPN+sVCAM1+AGP+SAA.

CONCLUSIONS

These results suggest that several serum proteins are directly related to the severity of gastric cancer. Overall, stronger associations are observed with metastatic than non-metastatic GA as the protein changes are greater with the metastatic status. A combination of these serum proteins may serve as non-invasive markers to assess the severity status and stage of gastric cancer.

Association between preeclampsia and the CXC chemokine family (Review)

Preeclampsia is a major cause of maternal and perinatal mortality and morbidity, characterized by gestational hypertension, proteinuria, systemic endothelial cell activation and an exaggerated inflammatory response. The precise cause of preeclampsia is not currently known; however, it is widely accepted that the pathogenesis of preeclampsia involves inadequate trophoblast invasion, leading to generalized endothelial dysfunction and an exaggerated inflammatory response. Chemokines are a superfamily of structurally similar proteins that mediate cell recruitment, angiogenesis, immunity and stem cell trafficking. CXC chemokines are a family of cytokines, unique in their ability to behave in a disparate manner in the regulation of angiogenesis. The CXC chemokine family further divides into two subfamilies; CXC ELR+, which promotes angiogenesis, and CXC ELR-, which inhibits angiogenesis. Furthermore, CXC chemokines are involved in the pathogenesis of various conditions, including malignant tumors, wound repair, chronic inflammation, atherosclerosis and potentially preeclampsia.

Myeloid derived hypoxia inducible factor 1-alpha is required for protection against pulmonary Aspergillus fumigatus infection

Hypoxia inducible factor 1α (HIF1α) is the mammalian transcriptional factor that controls metabolism, survival, and innate immunity in response to inflammation and low oxygen. Previous work established that generation of hypoxic microenvironments occurs within the lung during infection with the human fungal pathogen Aspergillus fumigatus. Here we demonstrate that A. fumigatus stabilizes HIF1α protein early after pulmonary challenge that is inhibited by treatment of mice with the steroid triamcinolone. Utilizing myeloid deficient HIF1α mice, we observed that HIF1α is required for survival and fungal clearance early following pulmonary challenge with A. fumigatus. Unlike previously reported research with bacterial pathogens, HIF1α deficient neutrophils and macrophages were surprisingly not defective in fungal conidial killing. The increase in susceptibility of the myeloid deficient HIF1α mice to A. fumigatus was in part due to decreased early production of the chemokine CXCL1 (KC) and increased neutrophil apoptosis at the site of infection, resulting in decreased neutrophil numbers in the lung. Addition of recombinant CXCL1 restored neutrophil survival and numbers, murine survival, and fungal clearance. These results suggest that there are unique HIF1α mediated mechanisms employed by the host for protection and defense against fungal pathogen growth and invasion in the lung. Additionally, this work supports the strategy of exploring HIF1α as a therapeutic target in specific immunosuppressed populations with fungal infections.

In vivo effects of lattice radiation therapy on local and distant lung cancer: potential role of immunomodulation

Radiation is a potent immune-modulator that elicits cell death upon tumor, stromal and angiogenic compartments of tumor microenvironment. Here, we test a novel approach of high-dose radiation delivery using three dimensional volume based lattice radiation therapy (LRT) to understand the impact of different volume irradiation in eliciting both local and metastatic/distant tumor control through modulation of tumor immune micro-environment. To study such effects of LRT, tumors were implanted in both hind legs of C57BL/6 mice using Lewis lung carcinoma 1 (LLC1) cells. Mice were divided into five groups: untreated; partial tumor volume groups included two 10% vertices, one 20% vertex and one 50% vertex of the total tumor volume; and 100% open-field irradiation. Tumors implanted in the left flank were irradiated with a single dose of 20 Gy while the tumors in the right flank were unirradiated. Tumor growth and regression as well as immune responses (such as Th1 and Th2; T-cell infiltration) were determined after radiation treatment. Results demonstrated that both 100% open-field irradiation and 20% volume irradiation (in two 10% volumes) resulted in significant growth delay in the irradiated tumor. Further, all types of radiation exposures, partial or 100% volume, demonstrated distal effectiveness, however, 20% volume irradiation (in two 10% volumes) and 50% tumor volume irradiation led to maximum growth delay. Mice treated with partial tumor volume radiation induced a robust IFN-γ and Th1 response when compared to whole-tumor irradiation and down-modulated Th2 functions. The presence of increased CD3+ cells and TRAIL in partially irradiated tumor volumes correlated well with tumor growth delay. Further, serum obtained from any of the LRT treated mice caused growth inhibition of endothelial cells when compared to serum obtained from either untreated or open-field irradiated groups. These results indicate that high-dose partial volume irradiation can cause an improved distant effect than the total tumor volume irradiation through activating the host immune system.

Complement anaphylatoxins as immune regulators in cancer

The role of the complement system in innate immunity is well characterized. However, a recent body of research implicates the complement anaphylatoxins C3a and C5a as insidious propagators of tumor growth and progression. It is now recognized that certain tumors elaborate C3a and C5a and that complement, as a mediator of chronic inflammation and regulator of immune function, may in fact foster rather than defend against tumor growth. A putative mechanism for this function is complement-mediated suppression of immune effector cells responsible for immunosurveillance within the tumor microenvironment. This paradigm accords with models of immune dysregulation, such as autoimmunity and infectious disease, which have defined a pathophysiological role for abnormal complement signaling. Several types of immune cells express the cognate receptors for the complement anaphylatoxins, C3aR and C5aR, and demonstrate functional modulation in response to complement stimulation. In turn, impairment of antitumor immunity has been intimately tied to tumor progression in animal models of cancer. In this article, the literature was systematically reviewed to identify studies that have characterized the effects of the complement anaphylatoxins on the composition and function of immune cells within the tumor microenvironment. The search identified six studies based upon models of lymphoma and ovarian, cervical, lung, breast, and mammary cancer, which collectively support the paradigm of complement as an immune regulator in the tumor microenvironment.

Targeted gene silencing using a follicle-stimulating hormone peptide-conjugated nanoparticle system improves its specificity and efficacy in ovarian clear cell carcinoma in vitro

BACKGROUND

RNA interference technology has shown high therapeutic potential for cancer treatment. However, serum instability, poor tissue permeability and non-specific uptake of short interfering RNA (siRNA) limit its administration in vivo. To overcome these limitations and improve the specificity for ovarian cancer, we developed a targeted nanoparticle delivery system for siRNA. This system included follicle-stimulating hormone (FSH) β 33-53 peptide as a targeting moiety that specifically recognized FSH receptor (FSHR) expressed on ovarian cancer cells. Growth regulated oncogene α (gro-α) has been reported to be involved in ovarian cancer development and progression. Thus, siRNA targeted to gro-α was used as an antitumor drug in this delivery system.

METHODS

FSH β 33-53 peptide-conjugated gro-α siRNA-loaded polyethylene glycol (PEG)-polyethylenimine (PEI) nanoparticles (FSH33-G-NP) were prepared and characterized by gel retardation assay and transmission electron microscopy. Particle size and zeta potential were determined. Expression of gro-α mRNA and protein was detected by real-time quantitative RT-PCR, immunocytochemistry and enzyme-linked immunosorbent assay. The proliferation, migration and invasion of the ovarian clear cell carcinoma cell line ES-2 were evaluated by cell counting kit-8 assay, cell scratch assay and transwell migration assay.

RESULTS

A siRNA sequence that is effective in silencing gro-α expression was obtained and loaded into the targeted delivery system. Compared with gro-α siRNA-loaded nanoparticles without FSH peptide modification (G-NP), FSH33-G-NP significantly down-regulated gro-α expression in ES-2 cells at mRNA and protein levels. Consequently, the aggressive biological behaviors of ES-2 cells, including proliferation, migration and invasion, were suppressed after silencing gro-α expression, and the addition of the FSH β 33-53 peptide enhanced the suppressive effects.

CONCLUSIONS

This study indicated that a FSHR-mediated delivery system could mediate the highly selective delivery of siRNA into ovarian cancer cells and that silencing gro-α expression could be a potential choice for ovarian cancer treatment.

Signaling Networks of Activated Oncogenic and Altered Tumor Suppressor Genes in Head and Neck Cancer

Head and neck squamous cell carcinoma (HNSCC) arises from the upper aerodigestive tract and is the six most common cancers worldwide. HNSCC is associated with high morbidity and mortality, as standard surgery, radiation, and chemotherapy can cause significant disfigurement and only provide 5-year survival rates of ~50-60%. The heterogeneity of HNSCC subsets with different potentials for recurrence and metastasis challenges the traditional pathological classification system, thereby increasing demand for the development of new diagnostic, prognostic, and therapeutic tools based on global molecular signatures of HNSCC. Historically, using classical biological techniques, it has been extremely difficult and time-consuming to survey hundreds or thousands of genes in a given disease. However, the development of high throughput technologies and high-powered computation throughout the last two decades has enabled us to investigate hundreds or thousands of genes simultaneously. Using high throughput technologies, our laboratory has identified the gene signatures and protein networks, which significantly affect HNSCC malignant phenotypes, including TP53/p63/p73 family members, IL-1/TNF-β/NF-κB, PI3K/AKT/mTOR, IL-6/IL-6R/JAK/STAT3, EGFR/MAPK/AP1, HGF/cMET/EGR1, and TGFβ/TGFβR/TAK1/SMAD pathways. This review summarizes the results from high-throughput technological assays conducted on HNSCC samples, including microarray, DNA methylation, miRNA profiling, and protein array, using primarily experimental data and conclusions generated in our own laboratory. The use of bioinformatics and integrated analyses of data sets from different platforms, as well as meta-analysis of large datasets pulled from multiple publicly available studies, provided significantly higher statistical power to extract biologically relevant information. The data suggested that the heterogeneity of HNSCC genotype and phenotype are much more complex than we previously thought. Understanding of global molecular signatures and disease classification for specific subsets of HNSCC will be essential to provide accurate diagnoses for targeted therapy and personalized treatment, which is an important effort toward improving patient outcomes.

CXC chemokine KC fails to induce neutrophil infiltration and neoangiogenesis in a mouse model of myocardial infarction

BACKGROUND

Chemokines and neutrophils, known as important players in the inflammatory cascade, also contribute to heart tissue recovery and scar formation after myocardial infarction (MI). The objective of this study was to determine the importance of ELR-containing CXC chemokine KC in neutrophil infiltration and neoangiogenesis, in a mouse model of chronic MI.

METHODS AND RESULTS

MI was induced in mice divided in four groups: control (untreated), anti-KC "later" (anti-KC antibody injections started 4 days after MI and then delivered every 72 hours for 3 weeks, to inhibit angiogenesis), anti-KC "earlier" (anti-KC antibody injections 1 day before and 1 day after MI, to block neutrophil infiltration), anti-KC (anti-KC antibody injections 1 day before and 1 day after MI, and then every 72 hours for 3 weeks). The efficiency of the anti-KC treatment was determined by the measurement of KC serum concentration and immunofluorescence staining, in each of the four groups. Surprisingly, we did not find any difference in neutrophil infiltration in the infarcted area between untreated and treated animals. Moreover, the heart function, infarct size, and neoangiogenesis were not different between the four groups. As expected, a comparable anti-CXCR2 treatment of mice before and after MI was able to significantly reduce neutrophil infiltration into the infarcted area and angiogenesis, but also to reduce the infarction size after long or "later" treatment.

CONCLUSIONS

The major finding of our study is that KC, a potent neutrophil chemoattractant and an established angiogenic factor, failed to interfere in the post-infarction inflammatory response, in wound healing and scar formation after MI. Therefore, these aspects need to be carefully taken into account when devising therapeutic strategies for myocardial infarction and ischemic cardiomyopathy.

Mesenchymal stem cells tune the development of monocyte-derived dendritic cells toward a myeloid-derived suppressive phenotype through growth-regulated oncogene chemokines

Mesenchymal stem/stromal cells (MSCs) are promising potential candidates for the treatment of immunological diseases because of their immunosuppressive functions. However, the molecular mechanisms that mediate MSCs' immunosuppressive activity remain elusive. In this article, we report for the first time, to our knowledge, that secreted growth-regulated oncogene (GRO) chemokines, specifically GRO-γ, in human MSC-conditioned media have an effect on the differentiation and the function of human monocyte-derived dendritic cells. The monocyte-derived dendritic cells were driven toward a myeloid-derived suppressor cell (MDSC)-like phenotype by the GRO chemokines. GRO-γ-treated MDSCs had a tolerogenic phenotype that was characterized by an increase in the secretion of IL-10 and IL-4, and a reduction in the production of IL-12 and IFN-γ. We have also shown that the mRNA expression levels of the arginase-1 and inducible NO synthase genes, which characterize MDSCs, were upregulated by GRO-γ-primed mouse bone marrow cells. In addition, the ability of GRO-γ-treated bone marrow-derived dendritic cells to stimulate the OVA-specific CD8(+) T (OT-1) cell proliferation and the cytokine production of IFN-γ and TNF-α were significantly decreased in vivo. Our findings allow a greater understanding of how MDSCs can be generated and offer new perspectives to exploit the potential of MDSCs for alternative approaches to treat chronic inflammation and autoimmunity, as well as for the prevention of transplant rejection.