Erythroid Differentiation Regulator 1, an Interleukin 18-Regulated Gene, Acts as a Metastasis Suppressor in Melanoma

Erdr1 Drives Macrophage Programming via Dynamic Interplay with YAP1 and Mid1

Erythroid differentiation regulator 1 (Erdr1) is a stress-induced, widely expressed, highly conserved secreted factor found in both humans and mice. Erdr1 is linked with the Hippo-YAP1 signaling. Initially identified as an inducer of hemoglobin synthesis, Erdr1 emerged as a multifunctional protein, especially in immune cells. Although Erdr1 has been implicated in regulating T cells and NK cell function, its role in macrophage remains unclear. This study explored the function and mechanism of Erdr1 in macrophage inflammatory response. The data demonstrated that Erdr1 could promote anti-inflammatory cytokine production, a function that also has been reported by previous research. However, I found Erdr1 also could play a proinflammatory role. The function of Erdr1 in macrophages depends on its dose and cell density. I observed that Erdr1 expression was inhibited in M1 macrophages but was upregulated in M2 macrophages compared with unpolarized macrophages. I hypothesized that Erdr1 balances the inflammatory response by binding with distinct adaptors dependent on varying concentrations. Mechanistically, I demonstrated YAP1 and Mid1 as the two adaptor proteins of Erdr1. The Erdr1-YAP1 interaction promotes anti-inflammatory cytokine production when Erdr1 levels are elevated, whereas the Erdr1-Mid1 interaction induces proinflammatory cytokine production when Erdr1 levels are decreased. This study highlights the effects of Erdr1 on regulating cytokine production from polarized macrophages potentially by regulating YAP1 in the nonclassical Hippo pathway.

Erdr1 orchestrates macrophage polarization and determines cell fate via dynamic interplay with YAP1 and Mid1

Erythroid differentiation regulator 1 (Erdr1) is a stress-induced, widely distributed, extremely conserved secreted factor found in both humans and mice. Erdr1 is highly linked with the Hippo-YAP1 signaling. Initially identified as an inducer of hemoglobin synthesis, it has emerged as a multifunctional protein, especially in immune cells. Although Erdr1 has been implicated in T cells and NK cell function, its role in macrophage remains unclear. This study aims to explore the function and mechanism of Erdr1 in IL-1β production in macrophages. Data manifest Erdr1 could play an inhibition role in IL-1β production, which also has been reported by previous research. What significance is we discovered Erdr1 can promote IL-1β production which is associated with Erdr1 dose and cell density. We observed that Erdr1 was inhibited in pro-inflammatory (M1) macrophages but was upregulated in anti-inflammatory (M2) macrophages compared to naive macrophages. We hypothesized that Erdr1 dual drives and modulates IL-1β production by binding with distinct adaptors via concentration change. Mechanistically, we demonstrated that Erdr1 dual regulates IL-1β production by dynamic interaction with YAP1 and Mid1 by distinct domains. Erdr1-YAP1 interplay mediates macrophage M2 polarization by promoting an anti-inflammatory response, enhancing catabolic metabolism, and leading to sterile cell death. Whereas, Erdr1-Mid1 interplay mediates macrophage M1 polarization by initiating a pro-inflammatory response, facilitating anabolic metabolism, and causing inflammatory cell death. This study highlights Erdr1 orchestrates macrophage polarization and determines cell date by regulating YAP1 through non-classical Hippo pathway.

Molecular Mechanisms of IL18 in Disease

Interleukin 18 (IL18) was originally identified as an inflammation-induced cytokine that is secreted by immune cells. An increasing number of studies have focused on its non-immunological functions, with demonstrated functions for IL18 in energy homeostasis and neural stability. IL18 is reportedly required for lipid metabolism in the liver and brown adipose tissue. Furthermore, IL18 (Il18) deficiency in mice leads to mitochondrial dysfunction in hippocampal cells, resulting in depressive-like symptoms and cognitive impairment. Microarray analyses of Il18-/- mice have revealed a set of genes with differential expression in liver, brown adipose tissue, and brain; however, the impact of IL18 deficiency in these tissues remains uncertain. In this review article, we discuss these genes, with a focus on their relationships with the phenotypic disease traits of Il18-/- mice.

Erythroid Differentiation Regulator 1 Strengthens TCR Signaling by Enhancing PLCγ1 Signal Transduction Pathway

Erythroid differentiation regulator 1 (Erdr1) has previously been reported to control thymocyte selection via TCR signal regulation, but the effect of Erdr1 as a TCR signaling modulator was not studied in peripheral T cells. In this report, it was determined whether Erdr1 affected TCR signaling strength in CD4 T cells. Results revealed that Erdr1 significantly enhanced the anti-TCR antibody-mediated activation and proliferation of T cells while failing to activate T cells in the absence of TCR stimulation. In addition, Erdr1 amplified Ca²⁺ influx and the phosphorylation of PLCγ1 in CD4 T cells with the TCR stimuli. Furthermore, NFAT1 translocation into nuclei in CD4 T cells was also significantly promoted by Erdr1 in the presence of TCR stimulation. Taken together, our results indicate that Erdr1 positively modulates TCR signaling strength via enhancing the PLCγ1/Ca²⁺/NFAT1 signal transduction pathway.

Erythroid Differentiation Regulator 1 Ameliorates Collagen-Induced Arthritis via Activation of Regulatory T Cells

Erythroid differentiation regulator 1 (Erdr1) has been identified as an anti-inflammatory factor in several disease models, including collagen-induced arthritis (CIA), but its exact mechanisms are still not fully understood. Here, the involvement of regulatory T (Treg) cells in Erdr1-improved CIA was investigated. In the CIA model, Erdr1 was confirmed to reduce collagen-specific IgM in plasma and plasma cells in draining lymph nodes. Importantly, the downregulated Treg cell ratio in draining lymph nodes from CIA mice was recovered by Erdr1 treatment. In addition, administration of Erdr1 improved the CIA score and joint tissue damage, while it revealed no effect in Treg cell-depleted CIA mice, indicating that Treg cells mediate the therapeutic effects of Erdr1 in the CIA model. Results from in vitro experiments also demonstrated that Erdr1 significantly induced Treg cell differentiation and the expression of Treg activation markers, including CD25, CD69, and CTLA4 in CD4⁺Foxp3⁺ cells. Furthermore, Erdr1-activated Treg cells dramatically suppressed the proliferation of responder T cells, suggesting that they are functionally active. Taken together, these results show that Erdr1 induces activation of Treg cells and ameliorates rheumatoid arthritis via Treg cells.

Erythroid differentiation regulator 1 promotes wound healing by inducing the production of C‑C motif chemokine ligand 2 via the activation of MAP kinases in vitro and in vivo

The erythroid differentiation regulator 1 (Erdr1) protein has been studied for its role in various inflammatory skin diseases, including skin cancer, actinic keratosis and psoriasis. However, the therapeutic effects of Erdr1 on wound repair and its underlying mechanisms remain unknown. The present study aimed to investigate the effects of Erdr1 on wound healing in vitro and in vivo. The results demonstrated that treatment with recombinant Erdr1 enhanced wound healing in vivo and in vitro. In addition, Erdr1 increased the proliferation and migration of human dermal fibroblasts (HDFs). Notably, Erdr1 significantly induced the production of the chemoattractant C-C motif chemokine ligand 2 (CCL2) and recruited immune cells involved in wound healing. Treatment with recombinant Erdr1 induced the activation of the ERK1/1, p38 and JNK1/2 mitogen-activated protein (MAP) kinases. Treatment with specific inhibitors for MAP kinase inhibitors markedly suppressed cell proliferation and migration, and inhibited the production of CCL2 in HDFs. Furthermore, the inhibition of CCL2 with a neutralizing antibody significantly suppressed the recombinant Erdr1-induced proliferation and migration of HDFs. The wound healing activity of Erdr1 was comparable to that of epidermal growth factor. Taken together, these results demonstrated that Erdr1 promoted the proliferation and migration of HDFs and exhibited potent wound healing properties mediated by CCL2. Therefore, the results of the present study suggested that Erdr1 may be a potential therapeutic target for promoting wound healing.

Update on the pathogenesis and management of ocular rosacea: an interdisciplinary review

PURPOSE

Rosacea is one of the most common conditions affecting the ocular surface. The purpose of this review is to provide an update on the pathogenesis and treatment of rosacea based on the dermatology and ophthalmology literatures.

METHODS

Literature searches were conducted for rosacea and ocular rosacea. Preference was given to systematic reviews, meta-analysis, case-controlled studies, and documented case reports while excluding poorly documented case studies and commentaries. The data were examined and independently analyzed by more than two of the authors.

RESULTS

Rosacea is a complex inflammatory condition involving the pilosebaceous unit. Its underlying mechanism involves an interplay of the microbiome, innate immunity, adaptive immunity, environmental triggers, and neurovascular sensitivity. The latest classification of rosacea includes three dermatologic subgroups and a fourth subgroup, ocular rosacea. Ocular rosacea clinically displays many features that are analogous to the cutaneous disease, such as lid margin telangiectasia and phlyctenulosis. The role of environmental triggers in the exacerbation of ocular rosacea appears to be understudied. While lid hygiene and systemic treatment with tetracycline drugs remain the mainstay of treatment for ocular rosacea, newer dermatologic targets and therapies may have potential application for the eye disease.

CONCLUSIONS

Ocular rosacea appears to embody many of the manifestation of the dermatologic disease. Hence, the basic pathophysiologic mechanisms of the ocular and cutaneous disease are likely to be shared. Better understanding of the ocular surface microbiome and the immunologic mechanisms, may lead to novel approaches in the management of ocular rosacea.

The Role of Erythroid Differentiation Regulator 1 (ERDR1) in the Control of Proliferation and Photodynamic Therapy (PDT) Response

Erythroid differentiation regulator 1 (ERDR1) was newly identified as a secreted protein that plays an essential role in maintaining cell growth homeostasis. ERDR1 enhances apoptosis at high cell densities, leading to the inhibition of cell survival. Exogenous ERDR1 treatment decreases cancer cell proliferation and tumor growth as a result of increased apoptosis via the regulation of apoptosis-related gene expression. Moreover, ERDR1 plays a pivotal role in skin diseases; ERDR1 expression in actinic keratosis (AK) is negatively correlated with the increase in apoptosis. Because of its high specificity and efficiency, photodynamic therapy (PDT) is a common therapy for patients with various skin diseases, including cancer. Many studies indicate that apoptosis is mainly induced by PDT treatment. As an apoptosis inducer, the recovery of the ERDR1 expression after PDT is correlated with good therapeutic outcomes. Here, we review recent findings that highlight the function of ERDR1 in the control of apoptosis. Thus, ERDR1 may have a role in the apoptosis regulation of target cells in the lesions, as the recovery of its expression after PDT is correlated with good therapeutic outcomes.

Prostaglandin E2 Receptor 2 Modulates Macrophage Activity for Cardiac Repair

Background

Prostaglandin E₂ has long been known to be an immune modulator. It is released after tissue injury and plays a role in modulating macrophage activities, which are essential for tissue regeneration. However, the involvement of prostaglandin E₂ receptor 2 (EP2)–dependent regulation of macrophages in postischemic heart is unclear. This study aims to evaluate the role of EP2 in damaged heart.

Methods and Results

The effect of EP2 in postischemic heart was evaluated using EP2‐deficient transgenic mice. We demonstrated that cardiac function was worse after myocardial injury on loss of EP2. Furthermore, EP2 deficiency also altered proinflammatory response and resulted in a defect in macrophage recruitment to the injured myocardium. Transcriptome analysis revealed that the expression of erythroid differentiation regulator 1 (Erdr1) was significantly induced in EP2‐deficient macrophages. Knocking down Erdr1 expression restored migration ability of EP2‐deficient cells both in vitro and in vivo. By using a genetic fate‐mapping approach, we showed that abolishment of EP2 expression effectively attenuated cell replenishment.

Conclusions

The EP2‐dependent signaling pathway plays a critical role in regulating macrophage recruitment to the injured myocardium, thereby exerting a function in modulating the inflammatory microenvironment for cardiac repair.

Erythroid differentiation regulator 1 strengthens TCR signaling in thymocytes by modulating calcium flux

Erythroid differentiation regulator 1 (Erdr1) has been identified as a stromal survival factor released under stressful conditions. Previously, Erdr1 was reported to be expressed highly in thymus, but roles of Erdr1 in thymus were not known. Here, the effects of Erdr1 on T cell development were investigated. The expression of Erdr1 was higher in thymus than bone marrow and Erdr1 was detected in both the cortex and medulla of thymus. Erdr1 treatment significantly induced the expression of activation marker, CD69, from thymocytes in the presence of TCR stimuli in vitro and the induction was dependent on increased Ca²⁺ influx. In addition, in vivo administration of Erdr1 resulted in significant increase of total and positive selected thymocyte numbers, particularly in the number of CD3TCR^hiCD69⁺ DP thymocytes. Taken together, our results show that Erdr1 enhances the strength of TCR signaling and cellularity of thymocytes by amplifying Ca²⁺ influx in thymocytes receiving TCR signals.

Commensal regulation of T cell survival through Erdr1

The commensal microbiota influences many aspects of immune system regulation, including T cells, but molecular details of how this occurs are largely unknown. Here we review our findings that the microbiota regulates Erdr1, a secreted apoptotic factor, to control T cell survival. Erdr1 is highly upregulated in CD4+ T cells from germfree mice and antibiotic treated animals, and our study shows that Erdr1 is suppressed by the microbiota via Toll-like receptor signaling and MyD88 dependent pathways. Erdr1 functions in an autocrine fashion and promotes apoptosis through the FAS/FASL pathway. Suppression of Erdr1 leads to survival of autoreactive T cells and exacerbated autoimmune disease in the EAE model, and overexpression of Erdr1 results in lessened disease. This novel T cell apoptotic factor has implications for autoimmunity, cancer biology, and invasive pathogens and thus represents a novel therapeutic target in disease.

Microbiota promotes systemic T-cell survival through suppression of an apoptotic factor

Symbiotic microbes impact the severity of a variety of diseases through regulation of T-cell development. However, little is known regarding the molecular mechanisms by which this is accomplished. Here we report that a secreted factor, Erdr1, is regulated by the microbiota to control T-cell apoptosis. Erdr1 expression was identified by transcriptome analysis to be elevated in splenic T cells from germfree and antibiotic-treated mice. Suppression of Erdr1 depends on detection of circulating microbial products by Toll-like receptors on T cells, and this regulation is conserved in human T cells. Erdr1 was found to function as an autocrine factor to induce apoptosis through caspase 3. Consistent with elevated levels of Erdr1, germfree mice have increased splenic T-cell apoptosis. RNA sequencing of Erdr1-overexpressing cells identified the up-regulation of genes involved in Fas-mediated cell death, and Erdr1 fails to induce apoptosis in Fas-deficient cells. Importantly, forced changes in Erdr1 expression levels dictate the survival of auto-reactive T cells and the clinical outcome of neuro-inflammatory autoimmune disease. Cellular survival is a fundamental feature regulating appropriate immune responses. We have identified a mechanism whereby the host integrates signals from the microbiota to control T-cell apoptosis, making regulation of Erdr1 a potential therapeutic target for autoimmune disease.

Roles of Erythroid Differentiation Regulator 1 (Erdr1) on Inflammatory Skin Diseases

Erythroid Differentiation Regulator 1 (Erdr1) is known as a hemoglobin synthesis factor which also regulates cell survival under conditions of stress. In addition, previous studies have revealed the effects of Erdr1 on cancer progression and its negative correlation with interleukin (IL)-18, a pro-inflammatory cytokine. Based on this evidence, the therapeutic effects of Erdr1 have been demonstrated in several inflammatory skin diseases such as malignant skin cancer, psoriasis, and rosacea. This article reviews the roles of Erdr1 in skin inflammation, suggesting that Erdr1 is a potential therapeutic molecule on inflammatory disorders.

Rosacea: Molecular Mechanisms and Management of a Chronic Cutaneous Inflammatory Condition

Rosacea is a chronic cutaneous inflammatory disease that affects the facial skin. Clinically, rosacea can be categorized into papulopustular, erythematotelangiectatic, ocular, and phymatous rosacea. However, the phenotypic presentations of rosacea are more heterogeneous. Although the pathophysiology of rosacea remains to be elucidated, immunologic alterations and neurovascular dysregulation are thought to have important roles in initiating and strengthening the clinical manifestations of rosacea. In this article, we present the possible molecular mechanisms of rosacea based on recent laboratory and clinical studies. We describe the genetic predisposition for rosacea along with its associated diseases, triggering factors, and suggested management options in detail based on the underlying molecular biology. Understanding the molecular pathomechanisms of rosacea will likely aid toward better comprehending its complex pathogenesis.

A Versatile Strategy for Isolating a Highly Enriched Population of Intestinal Stem Cells

The isolation of pure populations of mouse intestinal stem cells (ISCs) is essential to facilitate functional studies of tissue homeostasis, tissue regeneration, and intestinal diseases. However, the purification of ISCs has relied predominantly on the use of transgenic reporter alleles in mice. Here, we introduce a combinational cell surface marker-mediated strategy that allows the isolation of an ISC population transcriptionally and functionally equivalent to the gold standard Lgr5-GFP ISCs. Used on reporter-free mice, this strategy allows the isolation of functional, transcriptionally distinct ISCs uncompromised by Lgr5 haploinsufficiency.

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Reporter-free method to purify intestinal stem cells (ISCs)

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Cells share molecular signature with gold standard Lgr5-GFP high cells

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Multidimensional FACS data analysis reveals structure of intestinal crypt

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Lgr5 haploinsufficiency with functional consequences in ISCs from reporter mice

Therapeutic Effects of Erythroid Differentiation Regulator 1 on Imiquimod-Induced Psoriasis-Like Skin Inflammation

Psoriasis is a common skin disease accompanied by chronic inflammation. In previous studies, erythroid differentiation regulator 1 (ERDR1) was shown to have a negative correlation with proinflammatory cytokine IL-18. However, the role of ERDR1 in the inflammatory skin disease psoriasis has not been evaluated. In this study, to investigate the role of ERDR1 in psoriasis, recombinant ERDR1 was injected intraperitoneally into a psoriasis mouse model. Recombinant ERDR1 (rERDR1) significantly alleviated the symptoms of psoriasis-like skin inflammation and reduced the mRNA of various psoriasis-related markers, including keratin 14, S100A8, and Th17-related cytokines IL-17 and IL-22, suggesting that rERDR1 exerts therapeutic effects on psoriasis via the regulation of Th17 functions. Additionally, the expression of CCL20, a well-known Th17 attracting chemokine, was determined. CCL20 expression significantly decreased in the rERDR1-injected group compared with the vehicle (PBS)-injected group. CCR6 expression in the psoriatic lesional skin was also decreased by rERDR1 administration, implying the inhibition of CCR6-expressing Th17 cell chemotaxis via the downregulation of CCL20. Taken together, this study provides the first evidence that ERDR1 may be a potential therapeutic target for psoriasis.

Erdr1 Suppresses Murine Melanoma Growth via Regulation of Apoptosis

Melanoma, one of the aggressive cancers, is known to be resistant to chemotherapy. Because of its aggressive nature, effectively inducing apoptosis is necessary to treat melanoma. Erythroid differentiation regulator 1 (Erdr1) is known to be a stress-related survival factor exhibiting anti-cancer effects in several cancers. However, little is known about the functions and underlying mechanisms of Erdr1 so far. To demonstrate the effect of Erdr1 in melanoma apoptosis, recombinant murine Erdr1 was injected into mice implanted with B16F10 melanoma cells. In vivo tumor growth was significantly inhibited in mice injected with Erdr1 compared to the control. In addition, the tumor from Erdr1-injected mice showed an increased level of apoptosis. Accordingly, apoptosis-regulating factors including anti-apoptotic marker Bcl-2 and pro-apoptotic marker Bax in the tumor tissues were examined. As expected, the decreased level of Bcl-2 and increased level of Bax were detected in tumors within the mice injected with Erdr1. Based on the in vivo study, the role of Erdr1 in tumor apoptosis was further tested by incubating it with cells of the murine melanoma cell line B16F10. Erdr1-induced apoptosis in B16F10 cells was observed. Additionally, Erdr1 downregulated STAT3 activity, inhibiting apoptosis via regulation of the Bcl-2 family. Overall, data demonstrate that Erdr1 induced murine melanoma apoptosis through the regulation of Bcl-2 and Bax. These findings suggest that Erdr1 is a novel regulator of apoptosis in melanoma.

Recombinant erythroid differentiation regulator 1 inhibits both inflammation and angiogenesis in a mouse model of rosacea

The erythroid differentiation regulator 1 (Erdr1), which is a novel and highly conserved factor, was recently reported to be negatively regulated by IL-18 and to play a crucial role as an antimetastatic factor. IL-18 is a proinflammatory cytokine that functions as an angiogenic mediator in inflammation. Rosacea is a chronic inflammatory skin disorder that is characterized by abnormal inflammation and vascular hyperactivity of the facial skin. To determine whether Erdr1 contributes to the regulation of the chronic inflammatory process in the development of rosacea, an immunohistochemical analysis was performed in healthy donors and patients with rosacea. In this study, we showed that Erdr1 was downregulated, whereas IL-18 was upregulated, in patients with rosacea, which led us to question the role of Erdr1 in this disorder. Moreover, a rosacea-like BALB/c mouse model was used to determine the role of Erdr1 in rosacea in vivo. LL-37 injection induced typical rosacea features, including erythema, telangiectasia and inflammation. Treatment with recombinant Erdr1 (rErdr1) resulted in a significant reduction of erythema, inflammatory cell infiltration (including CD4(+) and CD8(+) T cells), and microvessel density with vascular endothelial growth factor (VEGF). Taken together, our findings suggest that rErdr1 may be involved in attenuating the inflammation and angiogenesis associated with the pathogenesis of rosacea. Thus, these results provide new insight into the mechanism involved in this condition and indicate that rErdr1 could be a potential target for therapeutic intervention of rosacea.

ERDR1 enhances human NK cell cytotoxicity through an actin-regulated degranulation-dependent pathway

Erythroid differentiation regulator 1 (ERDR1), which is a stress-related survival factor, exhibits anti-cancer effects against melanoma. However, the function of ERDR1 on immune cells has not been examined. We investigated whether ERDR1 regulates the cytotoxic ability of human natural killer (NK) cells, which are known as innate effector lymphocytes. In this study, treatment with recombinant ERDR1 resulted in enhanced NK cell cytotoxicity through the secretion of lytic granules. Furthermore, actin modulation was involved in the ERDR1-enhanced NK cell cytotoxicity. ERDR1 stimulated actin accumulation at the immunological synapse, which was induced by the activation of Vav-1 in NK cells. These findings suggest new insight into the function of ERDR1 function in the human immune system.

Application of neutrophil/lymphocyte ratio in predicting coronary blood flow and mortality in patients with ST-elevation myocardial infarction undergoing percutaneous coronary intervention

BACKGROUND

To investigate the potential correlation of neutrophil/lymphocyte ratio (NLR) to coronary blood flow and in-hospital along with long-term mortality in patients with ST-elevation myocardial infarction (STEMI) undergoing percutaneous coronary intervention (PCI).

METHODS

In the current study, 636 consecutive patients with STEMI were recruited and stratified into three tertiles by NLRs upon admission (tertile I<3.0, tertile II 3.0-6.40, tertile III>6.40). The coronary blood flow was expressed by corrected TIMI frame count (CTFC). The in-hospital mortality and 12-month long follow-up data were collected. Receiver operating characteristic (ROC) curves were also constructed.

RESULTS

Our analysis demonstrated that NLR was positively correlated to CTFC and in-hospital mortality (r=0.517, p<0.001; r=0.439, p<0.001). In the multiple logistic regression analysis, NLR was testified as an independent risk factor for coronary blood flow after PCI and in-hospital mortality [odds ratio (OR)=2.031, 95% confidence interval (CI): 1.627-2.435, p<0.001; OR=1.176, 95% CI: 1.025-1.351, p=0.021]. During the 12-month follow-up, there were a total of 43 deaths and statistically significant increase in long-term mortality was observed in patients from tertile I to III (p=0.005). In the ROC curves analysis, the area under the curve (AUC=0.607, 95% CI: 0.475-0.739, p=0.253), with threshold value of 5.9 (sensitivity: 63.7%, specificity: 61.1%) for predicting in-hospital mortality.

CONCLUSIONS

NLR, an indicator that can be tested in the laboratory with low cost and time consumption, is independently correlated to coronary blood flow and acts as an independent risk factor for in-hospital mortality in patients with STEMI undergoing PCI.

Aging enhances classical activation but mitigates alternative activation in the central nervous system

The roles of microglia and macrophages during neuroinflammation and neurodegenerative diseases remain controversial. To date, at least 2 activations states have been suggested, consisting of a classical response (M1) and the alternative response (M2). Identifying selective biomarkers of microglia that representative their functional activation states may help elucidate disease course and enable a better understanding of repair mechanisms. Two cocktails containing either tumor necrosis factor (TNF)-α, interleukin (IL)-12, and IL-1β (referred to as CKT-1) or IL-13 and IL-4 (referred to CKT-2) were injections into the hippocampus of mice aged 6, 12, or 24 months. Microarray analysis was performed on hippocampal tissue 3 days postinjection. Gene transcripts were compared between CKT-1 versus CKT-2 stimulator cocktails. Several selective transcripts expressed for the CKT-1 included CXCL13, haptoglobin, MARCO, and calgranulin B, whereas a smaller subset of genes was selectively induced by the CKT-2 and consisted of FIZZ1, IGF-1, and EAR 11. Importantly, selective transcripts were induced at all ages by CKT-1, whereas selective gene transcripts induced by CKT-2 decreased with age suggesting an age-related reduction in the IL-4/ IL-13 signaling pathway.

C-C chemokine receptor 5 on pulmonary mesenchymal cells promotes experimental metastasis via the induction of erythroid differentiation regulator 1

C-C Chemokine receptor 5 knockout (Ccr5(-/-)) mice develop fewer experimental pulmonary metastases than wild-type (WT) mice. This phenomenon was explored by applying gene expression profiling to the lungs of mice with these metastases. Consequently, erythroid differentiation regulator 1 (Erdr1) was identified as upregulated in the WT mice. Though commonly associated with bone marrow stroma, Erdr1 was differentially expressed in WT pulmonary mesenchymal cells (PMC) and murine embryonic fibroblasts (MEF). Moreover, the Ccr5 ligand Ccl4 increased its expression by 3.36 ± 0.14-fold. Ccr5 signaling was dependent on the mitogen-activated protein kinase kinase (Map2k) but not the phosphoinositide 3-kinase (Pi3k) pathway because treatment with U0126 inhibited upregulation of Erdr1, but treatment with LY294002 increased the expression by 3.44 ± 0.92-fold (P < 0.05). The effect Erdr1 on B16-F10 melanoma metastasis was verified by the adoptive transfer of WT MEFs into Ccr5(-/-) mice. In this model, MEFs that had been transduced with Erdr1 short hairpin RNA (shRNA) lowered metastasis by 33% compared with control transduced MEFs. The relevance of ERDR1 on human disease was assessed by coculturing chronic lymphocytic leukemia (CLL) cells with M2-10B4 stromal cells that had been transfected with shRNA or control plasmids. After 96 hours of coculture, the cell counts were higher with control cell lines than with Erdr1 knockdown lines [odds ratio (OR), 1.88 ± 0.27, 2.52 ± 0.66, respectively]. This increase was associated with a decrease in apoptotic cells (OR, 0.69 ± 0.18, 0.58 ± 0.12, respectively).

IMPLICATIONS

Therefore, ERDR1 is a stromal-derived factor that promotes cancer cell survival in vitro and in an experimental metastasis model.

Downregulation of erythroid differentiation regulator 1 as a novel marker of skin tumors

BACKGROUND

Erythroid differentiation regulator 1 is decreased in malignant melanoma. However, the expression of erythroid differentiation regulator 1 has not been reported in normal epidermis, vessel, nerve, dermal adnexae, and various skin tumors.

METHODS

To investigate the expression of erythroid differentiation regulator 1 in normal skin and various skin tumors, immunohistochemical analysis of normal skin, epidermal tumors, sebaceous tumors, and eccrine tumors was performed. The image analysis was quantitatively performed using HistoQuant(™) software.

RESULTS

Erythroid differentiation regulator 1 was strongly expressed in the nuclei of normal epidermis, sebaceous gland, eccrine gland, vessel, and nerve. Expression of erythroid differentiation regulator 1 was weak in seborrheic keratosis, sebaceous hyperplasia, and eccrine spiradenoma. Erythroid differentiation regulator 1 was rarely observed in malignant skin tumors, including squamous cell carcinoma, basal cell carcinoma, malignant melanoma, sebaceous carcinoma, and eccrine porocarcinoma.

CONCLUSIONS

The expression of erythroid differentiation regulator 1 was negatively correlated with the malignant potential in various skin tumors. The results support the role of erythroid differentiation regulator 1 in cutaneous carcinogenesis and indicate its potential as a novel marker of skin tumors.

Immunotherapeutic approach for better management of cancer--role of IL-18

Interleukin-18 (IL-18) is an immune-stimulatory cytokine with antitumor activity in preclinical models. It plays pivotal roles in linking inflammatory immune responses and tumor progression and is a useful candidate in gene therapy of lymphoma or lymphoid leukemia. A phase I study of recombinant human IL-18 (rhIL-18) in patients with advanced cancer concluded that rhIL-18 can be safely given in biologically active doses to patients with advanced cancer. Some viruses can induce the secretion of IL-18 for immune evasion. The individual cytokine activity might be potentiated or inhibited by combinations of cytokines. Here we focus on combinational effects of cytokines with IL-18 in cancer progression. IL-18 is an important non-invasive marker suspected of contributing to metastasis. Serum IL-18 may a useful biological marker as independent prognostic factor of survival. In this review we cover roles of IL-18 in immune evasion, metastasis and angiogenesis, applications for chemotherapy and prognostic or diagnostic significance.

Recombinant Erdr1 suppresses the migration and invasion ability of human gastric cancer cells, SNU-216, through the JNK pathway

Erythroid differentiation regulator 1 (Erdr1) suppressed cell motility in vitro and has anti-metastatic effect in vivo on melanoma. The current study investigated the effect of recombinant Erdr1 on the migration and invasion ability of SNU-216 cell, a gastric cancer cell line. The expression of Erdr1 is inversely correlated with IL-18 expression, which has a pro-cancer effect in gastric cancer. Treatment with rErdr1 markedly suppressed the ability of SNU-216 cells to migrate and invade, indicating that recombinant Erdr1 inhibited the motility of gastric cancer cells. E-cadherin expression levels were measured to determine the factor involved in the rErdr1-suppressed motility. E-cadherin is a representative of the cadherin family, known as cell motility enhancement adhesion molecule. Our results revealed that E-cadherin levels were increased by rErdr1 treatment, suggesting the involvement of E-cadherin in rErdr1-reduced cell migration. The cells were treated with specific MAPK inhibitors such as SP600125, SB203580 or PD98059 to identify the signaling mechanism involved with rErdr1 suppressed cell migration. The results indicated that the rErdr1 inhibited migration was primarily reversed by SP600125, a JNK inhibitor. In addition, the level of JNK phosphorylation was markedly increased by recombinant Erdr1. Taken together, these findings suggest that rErdr1 suppressed the ability of gastric cancer cells to metastasis by up regulating E-cadherin through a JNK pathway activation. Furthermore, it can be suggested that the inhibitory effect of recombinant Erdr1 on SNU-216 cell's metastatic potential was through cell motility suppression.