Soluble Epidermal Growth Factor Research Articles

The Association between Circulating Cytokines and Body Composition in Frail Patients with Cardiovascular Disease.

The burden of cardiovascular disease and the percentage of frail patients in the aging population will increase. This study aims to assess the circulating levels of several cytokines in frail patients. This is an ancillary analysis of the FRAPICA trial. The ratio of men/women changed from robust through frail groups from 3:1 to 1:2. The groups are comparable in terms of age and body measurements analysis (weight, height, and BMI), yet the frail patients have significantly reduced fat-free mass, and more often have been diagnosed with diabetes. Frail patients have higher fibroblast growth factor basic (FGF basic) and follistatin levels (borderline significance). In multiple linear regression modeling of fat-free mass, we identified FGF basic, osteopontin, stem cell factor, soluble suppression of tumorigenicity 2, soluble epidermal growth factor receptor, soluble human epidermal growth factor receptor 2, follistatin, prolactin, soluble interleukin 6 receptor alfa, platelet endothelial cell adhesion molecule 1, soluble vascular endothelial cell growth factor receptor 1, leptin, soluble angiopoietin/tyrosine kinase 2, and granulocyte colony-stimulating factor. We have identified a few cytokines that correlate with fat-free mass, a hallmark of frailty. They comprise the kinins implicated in bone and muscle metabolism, fibrosis, vascular wall function, inflammation, endocrine function, or regulation of bone marrow integrity.

Effect of cholesterol-lowering agents on soluble epidermal growth factor receptor level in type 2 diabetes and hypercholesterolemia.

Soluble epidermal growth factor receptor (sEGFR) levels are elevated in patients with type 2 diabetes mellitus (T2DM) and positively correlate with blood glucose and cholesterol levels. However, how cholesterol-lowering treatment in patients with T2DM affects the sEGFR level is unknown. Therefore, we investigated the change of serum sEGFR after cholesterol-lowering treatment in type 2 diabetic patients with hypercholesterolemia. This study is a non-randomized, prospective observational study. A total of 115 patients were treated in either the rosuvastatin monotherapy group (R group, 5 mg/day, n = 59) or the rosuvastatin/ezetimibe combination therapy group (RE group, 5 mg/10 mg/day, n = 56) for 12 weeks. We measured serum levels of lipids and sEGFR using an ELISA kit before and after 12 weeks of treatment in each group. The low-density lipoprotein cholesterol (LDL-C) level was significantly reduced (from 130.27 ± 27.09 to 76.24 ± 26.82 mg/dL; P < .001) after 12 weeks of treatment and more so in the RE group than in the R group (from 131.68 ± 28.72 to 87.13 ± 27.04 mg/dL, P < .001 in the R group; from 128.78 ± 25.58 to 64.75 ± 21.52 mg/dL, P < .001 in the RE group; R vs RE group, P < .001). The sEGFR level was significantly decreased after 12 weeks of treatment (from 50.34 ± 13.31 to 45.75 ± 11.54 ng/mL; P = .007). The RE group only showed a significant reduction in the sEGFR level after treatment (from 50.94 ± 12.10 to 44.80 ± 11.36 ng/mL; P = .007). Moreover, the sEGFR level was significantly reduced only when the LDL-C level was significantly reduced (from 50.46 ± 10.66 to 46.24 ± 11.86 ng/mL; P = .043). The serum sEGFR level was significantly reduced by cholesterol-lowering treatment with rosuvastatin alone or rosuvastatin/ezetimibe. We suggested that sEGFR may play a significant role in insulin resistance (IR) and inflammation, which are central pathophysiological mechanisms. We confirmed the possibility of using sEGFR as a biomarker to predict a good response to lipid-lowering treatment in type 2 diabetes patients with hypercholesterolemia.

Pan-cancer distribution of cleaved cell-surface amphiregulin, the target of the GMF-1A3 antibody drug conjugate.

Amphiregulin is a transmembrane protein which, when cleaved by the TACE/ADAM17 protease, releases a soluble epidermal growth factor receptor ligand domain that promotes proliferation of normal and malignant cells. We previously described a rabbit monoclonal antibody, GMF-1A3, that selectively recognizes the cell-associated cleaved amphiregulin epitope. Antibody-drug conjugates had anti-tumor activity against human breast cancer xenografts. Several tumor types express amphiregulin, but evidence for a functional requirement for amphiregulin in these malignancies is limited. By directly evaluating amphiregulin cleavage with immunohistochemistry, GMF-1A3 provides a more direct measure of amphiregulin activity. Using 370 specimens from 10 tumor types (as well as normal controls), we demonstrate that cleaved amphiregulin is widely expressed in solid tumors and is especially common (> 50% of cases) in breast, prostate, liver and lung cancer. As a potential companion diagnostic for this antibody-drug conjugate, this assay allows identification of tumors with high levels of the cleaved amphiregulin target.

Changes in serum angiogenic factors among patients with acute pain and subacute pain.

Screening serum biomarkers for acute and subacute pain is important for precise pain management. This study aimed to examine serum levels of angiogenic factors in patients with acute and subacute pain as potential biomarkers. Serum samples were collected from 12 healthy controls, 20 patients with postherpetic neuralgia (PHN), 4 with low back pain (LBP), and 1 with trigeminal neuralgia (TN). Pain intensity in these patients was evaluated using the visual analog scale (VAS). The serum concentrations of 11 angiogenic biomarkers were examined by Milliplex Map Human Angiogenesis Magnetic Bead Panel 2. The pain assessment from VAS showed that all patients showed moderate and severe pain. Among 11 angiogenic factors, osteopontin (OPN), thrombospondin-2 (TSP-2), soluble platelet endothelial cell adhesion molecule-1 (sPECAM-1), soluble urokinase-type plasminogen activator receptor (suPAR), and soluble epidermal growth factor receptors (sErbB2) were up-regulated and soluble interleukin-6 receptor α (sIL-6Rα) were down-regulated in patients with pain compared to the healthy participants (all P-values were < 0.005). Moreover, a linear regression model showed that the serum OPN concentration was correlated with pain intensity in patients with PHN (P = 0.03). There was no significant difference between the serum concentration of soluble epidermal growth factor receptors, sErbB3, soluble AXL, tenascin, and soluble neuropilin-1 in patients with acute and subacute pain and that of healthy controls. The results of this study provided new valuable insights into our understanding of angiogenic factors that may contribute to as mechanistic biomarkers of pain, and reveal the pathophysiological mechanism of pain.Clinical Trial Registration: www.chictr.org.cn, identifier ChiCTR2200061775.

Rapid, convenient, and highly sensitive detection of human hemoglobin in serum using a high-affinity bivalent antibody–enzyme complex

Human hemoglobin (Hb) is a biomarker of several diseases, and monitoring of Hb levels is required during emergent surgery. However, rapid and sensitive Hb detection methods are yet to be developed. The present study established a rapid, convenient, and highly sensitive detection method for Hb in human serum using a bivalent antibody–enzyme complex (AEC). AECs are promising sensing elements because of their ability to bind specific targets and their catalytic activity that produce signals. We recently reported a convenient and universal method to fabricate bivalent AECs with two antibody fragments, using the SpyCatcher/SpyTag system. The present study applied a bivalent AEC for highly sensitive and quantitative detection of human Hb. The bivalent anti-Hb AEC was successfully prepared by incubating both N- and C-terminus SpyCatcher-fused glucose dehydrogenase and SpyTag-fused anti-Hb single-chain variable fragments at 4 °C. As expected, the bivalent AEC for Hb with a multimeric structure showed higher affinity than the monovalent AEC, by means of avidity effects, unlike that for soluble epidermal growth factor receptor with a monomeric structure; this contributed to a great improvement in sensitivity. Finally, we established a rapid and wash-free homogeneous electrochemical detection system for Hb by integrating magnetic beads. The linear range of the system completely covered the clinically required Hb levels, even in human serum. This technology provides an ideal point-of-care test for Hb and other multimeric biomarkers.

Changing the Wound: Covalent Immobilization of the Epidermal Growth Factor.

Re-epithelialization of wounds is a critical element of wound closure. Growth factors have been used in combination with conventional wound management to promote closure, but the method of delivery has been limited to the topical application of ointment formulations. Cytoactive factors delivered in this way have short resident times in wounds and have met with limited success. Here, we demonstrate that methods used to covalently immobilize proteins on synthetic materials can be extended to immobilize cytoactive factors such as the epidermal growth factor (EGF) onto the wound beds of genetically diabetic mice that exhibit impaired healing. Full-thickness splinted excisional wounds were created in diabetic (db/db) mice with a well-defined silicone splint to limit wound contracture. Wound surfaces were treated with a reducing agent to expose sulfhydryl groups and subsequently treated with EGF modified with a heterobifunctional crosslinker. This allowed for the covalent immobilization of the EGF to the wound surface. The conjugation chemistry was validated in vitro and in vivo. In a separate group of mice, wounds were topically treated twice daily with soluble EGF. The mice were evaluated over 11 days for wound closure. This covalent immobilization strategy resulted in EGF being retained on the wound surface for 2 days and significantly increased epithelial wound closure by 20% compared to wounds treated with topical EGF or topical vehicle. Covalent immobilization was not only therapeutically effective but also delivered a markedly reduced load of growth factor to the wound surface compared to topical application (when only 180 ng of EGF was immobilized onto the wound surface in comparison with 7200 ng of topically applied EGF over a period of 11 days). No adverse effects were observed in treated wounds. Results obtained provide proof of concept for the effectiveness of covalent immobilization in the treatment of dysregulated wounds. The covalent immobilization of cytoactive factors represents a potentially transformative approach to the management of difficult chronic wounds.

Markers of tissue remodeling and inflammation in the white and brown adipose tissues of a model hibernator

The thirteen-lined ground squirrel is a model fat-storing hibernator that nearly doubles its weight in the fall to fuel metabolism with triglycerides throughout the winter months. Hibernator brown and white adipose tissue (BAT, WAT) are important to study in terms of their inflammatory profile and tissue remodeling mechanisms since controlled and natural regulation of these processes could inform new pharmacological interventions that limit oxidative stress and inflammation in the adipose tissues of humans suffering from obesity, promote non-shivering thermogenesis-mediated weight loss, or prevent tissue damage in transplantable organs emerging from cold-storage. Thus, markers of inflammation like cytokines and soluble receptors and tissue remodeling proteins such as matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) were investigated in normothermic, torpid, and arousing ground squirrels. Multiplex protein assays and western blotting revealed fewer changes in WAT compared to BAT. Pro-inflammatory IL-1α levels increased during torpor and soluble epidermal growth factor receptor protein levels increased during arousal in BAT. Given their known roles in other model systems, these proteins could regulate processes like adipogenesis, lipid catabolism, or cell motility. Decreased TIMP2 levels combined with maintained MMP2 or MMP3 protein levels suggested that BAT may avoid tissue remodeling until arousal. No changes in WAT inflammatory cytokines or soluble receptors as well as decreased MMP2 levels during torpor and arousal suggested inflammation and modification to the extracellular matrix is likely suppressed in WAT. This study emphasizes the fat-but-fit nature of the hibernating ground squirrel and the ability of its fat stores to suppress inflammation.

Engineering soluble artificial epidermal growth factor receptor mimics capable of spontaneous in vitro dimerization.

Epidermal growth factor receptor (EGFR) is a clinically validated target for a multitude of human cancers. The receptor is activated upon ligand binding through a critical dimerization step. Dimerization can be replicated in vitro by locally concentrating the receptor kinase domains on the surface of lipid-based vesicles. In this study we investigated the use of coiled coils to induce spontaneous receptor kinase domain dimerization in vitro to form non-membrane-bound artificial receptor mimics in solution. Two engineered forms of EGFR kinase domain fused to coiled coil complementary peptides were designed to self-associate upon mixing. Two fusion protein species (P3-EGFR and P4-EGFR) independently showed the same activity and polymerization profile known to exist with EGFR kinase domains. Upon mixing the two species, coiled coil heterodimers were formed that induced EGFR association to form dimers of the kinase domains. This was accompanied by 11.5-fold increase in the phosphorylation rate indicative of kinase domain activation equivalent to the levels achieved using vesicle localization and mimicking in vivo ligand-induced activation. This study presents a soluble tyrosine kinase receptor mimic capable of spontaneous in vitro activation that can facilitate functional and drug discovery studies for this clinically important receptor class.

Correlations between serum cetuximab and EGFR-related markers, and skin disorders in head and neck cancer patients.

Cetuximab inhibits epidermal growth factor receptor (EGFR) signaling in cancer and skin cells, thereby inducing anti-cancer effects and skin disorders. The present study aimed to evaluate the relationships between serum cetuximab and EGFR-related markers, and adverse effects in head and neck cancer patients. Thirty-four head and neck cancer patients receiving weekly intravenous cetuximab were enrolled. Serum cetuximab levels were determined just before dosing. Blood samples for determination of serum EGFR-related markers including soluble epidermal growth factor receptor (sEGFR) and interleukin-6 (IL-6) were obtained. The severities of skin disorders, their medications, and hypomagnesemia treatment were also assessed. Serum levels of cetuximab and sEGFR were negatively and positively correlated with that of IL-6, respectively. The serum cetuximab level was twofold higher in the patients with a grade 2-3 skin rash than with a grade 0-1 rash. The serum cetuximab cutoff value related to severe skin rash was 71μg/mL (sensitivity, 59%; and specificity, 94%). The use of a strong topical corticosteroid for skin rash was also associated with a higher serum cetuximab level. Serum levels of sEGFR and IL-6 had no correlations with the skin disorder severities or their medications. Hypomagnesemia treatment using intravenous magnesium sulfate was not related to serum cetuximab and EGFR-related markers. Head and neck cancer patients with a higher serum IL-6 level tended to have a lower serum cetuximab level. Serum cetuximab had positive correlations to skin rash severity and its medication in the study population.

Soluble EGFR, a hepatokine, and adipsin, an adipokine, are biomarkers correlated with distinct aspects of insulin resistance in type 2 diabetes subjects

BackgroundInsulin resistance can occur in all metabolic organs including the liver, adipose tissue, and skeletal muscles. Circulating soluble epidermal growth factor receptor (soluble EGFR) and adipsin levels are altered in obese diabetic mice and are possibly correlated with insulin resistance in both mice and humans. Here, we investigated the significance of soluble EGFR and adipsin as biomarkers for insulin resistance in Japanese subjects with type 2 diabetes.MethodsWe measured the soluble EGFR and adipsin levels in sera from 47 non-diabetic subjects and 106 subjects with type 2 diabetes using enzyme-linked immunosorbent assays (ELISAs) and analyzed the correlations between the soluble EGFR or adipsin levels and metabolic parameters in type 2 diabetes subjects. We also measured the gene expression levels of Egfr and Cfd (adipsin) in the liver, adipose tissue, and skeletal muscle in mice with/without obesity or diabetes.ResultsThe soluble EGFR levels were correlated with the fasting blood glucose level (P = 0.010), HOMA-IR (P = 0.035), HbA1c level (P = 0.007), HDL-cholesterol level (P = 0.044), and FIB-4 index (P = 0.017) after adjustments for age, sex, and total cholesterol levels. These factors are known to be related to hepatic insulin resistance. The serum adipsin levels were correlated with BMI (P < 0.001), waist circumference (P < 0.001), fasting serum insulin level (P = 0.001), HOMA-IR (P = 0.009), CPR-index (P = 0.045), and FIB-4 index (P = 0.007) after adjustments for age, sex and eGFR levels. Abdominal adiposity leads to the potentiation of these factors. The expression of Egfr was abundant in the liver, while Cfd was predominantly expressed in adipose tissue in mice.ConclusionsSoluble EGFR, a hepatokine, is correlated with insulin resistance in the liver, while adipsin, an adipokine, is associated with adipose insulin resistance.Trial registration: UMIN Clinical Trials Registry (www.umin.ac.jp), UMIN000020474. Registered 8 January 2016.

S-HBEGF/SIRT1 circuit-dictated crosstalk between vascular endothelial cells and keratinocytes mediates sorafenib-induced hand\u2013foot skin reaction that can be reversed by nicotinamide

Hand–foot skin reaction (HFSR), among the most significant adverse effects of sorafenib, has been limiting the clinical benefits of this frontline drug in treating various malignant tumors. The mechanism underlying such toxicity remains poorly understood, hence the absence of effective intervention strategies. In the present study, we show that vascular endothelial cells are the primary cellular target of sorafenib-induced HFSR wherein soluble heparin-binding epidermal growth factor (s-HBEGF) mediates the crosstalk between vascular endothelial cells and keratinocytes. Mechanistically, s-HBEGF released from vascular endothelial cells activates the epidermal growth factor receptor (EGFR) on keratinocytes and promotes the phosphorylation of c-Jun N-terminal kinase 2 (JNK2), which stabilizes sirtuin 1 (SIRT1), an essential keratinization inducer, and ultimately gives rise to HFSR. The administration of s-HBEGF in vivo could sufficiently induce hyper-keratinization without sorafenib treatment. Furthermore, we report that HBEGF neutralization antibody, Sirt1 knockdown, and a classic SIRT1 inhibitor nicotinamide could all significantly reduce the sorafenib-induced HFSR in the mouse model. It is noteworthy that nicotinic acid, a prodrug of nicotinamide, could substantially reverse the sorafenib-induced HFSR in ten patients in a preliminary clinical study. Collectively, our findings reveal the mechanism of vascular endothelial cell-promoted keratinization in keratinocytes and provide a potentially promising therapeutic strategy for the treatment of sorafenib-induced HFSR.

Expression of Human Epidermal Growth Factor in Escherichia coli by Intein Approach

Different approaches are used to express recombinant proteins without the requirement of post-translational modification in Escherichia coli (E. coli). Though E. coli may have a drawback in producing endotoxin, its short division time and high expression of the final product are significant in making use as a host to produce various recombinant proteins. Inteins have been discovered in multiples microorganisms in facilitating the expression of homologous proteins and it has been used as one of the crucial tools for the production of recombinant proteins due to its unique feature in auto-excising its fusion partner, which also known as exteins. In this communication, we employed a well-established gp41-1 mini-intein to facilitate the expression of epidermal growth factor (EGF). The study revealed that though the epidermal growth factor cannot be excised from the gp41-1 mini intein during the expression, it showed the capability of gp41-1 mini intein in processing intracellular expression of soluble EGF fusion protein. Different conditions for inducing the cleavage of exteins from inteins has been studied by many research groups, and reducing condition by using the DTT works well on the C-terminal cleavage of EGF from the gp41-1 mini intein. The final purified, different concentration of EGF was mixed with homemade aqueous cream and showed to be highly active in accelerating the healing rate of patients suffering from bedsores, diabetic foot ulcers and skin rupture.

The clinical value of the combined detection of sEGFR, CA125 and HE4 for epithelial ovarian cancer diagnosis.

This study aims to investigate the clinical value of combined detection of serum soluble epidermal growth factor receptor (sEGFR), cancer antigen 125 (CA125), and human epididymis protein 4 (HE4) in the diagnosis of epithelial ovarian cancer (EOC). From December 2017 to October 2018, the serum samples were obtained from the Affiliated Hospital of Xuzhou Medical University, with 30 patients as EOC group, 30 patients with benign ovarian neoplasms as benign group, and 17 healthy subjects as healthy group. Besides, among 30 EOC patients, 9 serum samples were obtained from pre-operative and post-operative EOC patients. The levels of serum sEGFR were detected by enzyme-linked immunosorbent assay (ELISA), while CA125 and HE4 were detected by enhanced chemiluminescence immunoassay (ECLIA). The diagnostic value was evaluated by receiver operating characteristic (ROC) curve analysis. The levels of serum sEGFR, CA125, and HE4 in EOC group were significantly higher than those in benign group (p<0.05) and healthy group (p<0.05). When using a single tumor marker, the CA125 shows the highest sensitivity (93.30%) and HE4 shows the highest specificity (97.87%). The specificity of combined detection of serum sEGFR, CA125, and HE4 was 100%, which was significantly higher than that using a single tumor marker. The area under the ROC curve (AUC) of combined detection of serum sEGFR, CA125, and HE4 (0.965) was much higher than that of the single detection and higher than that of combined detection of CA125 and HE4 (0.940). Moreover, the level of serum sEGFR in post-operative EOC group was significantly lower than that in the corresponding pre-operative EOC group (p<0.05). Our study shows that combined detection of serum sEGFR, CA125, and HE4 increases the specificity and efficiency in EOC diagnosis, indicating that sEGFR could be a potential biomarker for the diagnosis and prognosis of EOC.

Leader cell PLCγ1 activation during keratinocyte collective migration is induced by EGFR localization and clustering.

Re‐epithelialization is a critical step in wound healing and results from the collective migration of keratinocytes. Previous work demonstrated that immobilized, but not soluble, epidermal growth factor (EGF) resulted in leader cell‐specific activation of phospholipase C gamma 1 (PLCγ1) in HaCaT keratinocytes, and that this PLCγ1 activation was necessary to drive persistent cell migration. To determine the mechanism responsible for wound edge‐localized PLCγ1 activation, we examined differences in cell area, cell–cell interactions, and EGF receptor (EGFR) localization between wound edge and bulk cells treated with vehicle, soluble EGF, or immobilized EGF. Our results support a multistep mechanism where EGFR translocation from the lateral membrane to the basolateral/basal membrane allows clustering in response to immobilized EGF. This analysis of factors regulating PLCγ1 activation is a crucial step toward developing therapies or wound dressings capable of modulating this signal and, consequently, cell migration.

2088-P: Soluble EGFR and Adipsin Are Independent Serum Biomarkers for Insulin Resistance in Mouse and Human

We identified soluble epidermal growth factor receptor (sEGFR), a hepatokine, and Adipsin, a adipokine, by serum quantitative proteomics as common factors, whose protein levels were significantly reduced across 4, 8, 12, and 24 weeks of ages in obese diabetic db/db mice and were restored by treatment with liraglutide. In this study, we investigated the properties of sEGFR and Adipsin as biomarkers in mouse and human. In mice, the expression of EGFR and Adipsin were abundant in the liver and adipose tissue, respectively, and significantly reduced in db/db mice. The sEGFR and Adipsin were significantly decreased in sera of high-fat diet-fed mice and ob/ob mice. Next, we measured the sEGFR and Adipsin levels in sera from 47 nondiabetes subjects and 106 patients with type 2 diabetes, and analyzed the correlation with clinical parameters by using multiple linear regression analysis. No correlations were observed between sEGFR and Adipsin levels. The sEGFR levels were positively correlated with HbA1c, fasting blood glucose, and HOMA-IR, and the association was remained after adjustment for age and sex (β = 0.357, p &amp;lt; 0.001; β = 0.299, p &amp;lt; 0.001; β = 0.259, p = 0.004). The sEGFR levels were also positively correlated with T-chol, TG, LDL-chol, and AST after adjustment for age and sex (β = 0.378, p &amp;lt; 0.001; β = 0.275, p &amp;lt; 0.001; β = 0.235, p = 0.004; β = 0.202, p = 0.014). The Adipsin levels were positively correlated with BMI, waist circumference, fasting serum insulin, and HOMA-IR, and remained correlation after adjustment for age and sex (β = 0.532, p &amp;lt; 0.001; β = 0.475, p &amp;lt; 0.001; β = 0.383, p &amp;lt; 0.001; β = 0.342, p = 0.003). The Adipsin levels were also positively correlated with FIB-4 index (liver fibrosis index), and negatively correlated with eGFR after adjustment for age and sex (β = 0.264, p = 0.013; β = -0.352, p &amp;lt; 0.001). These findings suggest that sEGFR and Adipsin are independent biomarkers that correlate with factors for insulin resistance, and might reflect liver and fat insulin resistance, respectively. Disclosure M. Kyohara: None. J. Shirakawa: None. Y. Terauchi: Advisory Panel; Self; AstraZeneca, Daiichi Sankyo Company, Limited, Eli Lilly and Company, Merck Sharp &amp; Dohme Corp., Mitsubishi Tanabe Pharma Corporation, Novo Nordisk A/S, Sanofi. Research Support; Self; Daiichi Sankyo Company, Limited, Eli Lilly and Company, Merck Sharp &amp; Dohme Corp., Novartis Pharmaceuticals Corporation, Novo Nordisk A/S, Ono Pharmaceutical Co., Ltd., Sanofi, Shionogi &amp; Co., Ltd., Sumitomo Dainippon Pharma Co., Ltd. Speaker's Bureau; Self; Astellas Pharma Inc., AstraZeneca, Bayer Yakuhin, Ltd., Daiichi Sankyo Company, Limited, Eli Lilly and Company, Merck Sharp &amp; Dohme Corp., Mitsubishi Tanabe Pharma Corporation, Novartis Pharmaceuticals Corporation, Novo Nordisk A/S, Ono Pharmaceutical Co., Ltd., Sanofi, Sanwa Kagaku Kenkyusho, Shionogi &amp; Co., Ltd., Sumitomo Dainippon Pharma Co., Ltd.

Epidermal growth factor-nanoparticle conjugates change the activity from anti-apoptotic to pro-apoptotic at membrane rafts

The proliferation epidermal growth factor (EGF) is known to acquire contradictory apoptotic activities upon conjugation with gold nanoparticles (GNPs) through hitherto unknown mechanisms. Here, we identified an essential role of membrane rafts in the drastic activity switching of EGF-GNPs through the following intracellular signaling. (1) In contrast to the rapid diffusion of activated EGF receptor after the soluble EGF stimulation, the receptor is confined within membrane rafts upon binding to the EGF-GNPs. (2) This initial receptor confinements switch its endocytosis process from normal clathrin-mediated endocytosis to caveolin-mediated one, changing the phosphorylation dynamics of essential downstream kinases, i.e., extracellular signal-regulated kinase and AKT. Importantly, the destruction of membrane rafts by β-cyclodextrin reversed this trafficking and signaling, restoring EGF-GNPs to lost anti-apoptotic property. These results reveal the importance of GNP-mediated signal condensation at membrane rafts in conferring the unique apoptotic activity on EGF-nanoparticle conjugates. Statement of significanceEpidermal growth factor (EGF) is a small secretory protein that induces cell proliferation upon binding to its receptor existed on cellular plasma membranes. One interesting feature of the protein in the nanobiology field is, its acquisition of apoptosis-inducing (cellular suicide) activity rather than proliferative one upon conjugation to gold nanoparticles through hitherto unknown mechanisms. Here, we identified the involvement of membrane rafts, plasma membrane nanodomains enriched with cholesterol, in the apoptosis processes by changing the receptor trafficking and downstream signal transduction pathways. Moreover, the destruction of lipid rafts restored the EGF-nanoparticle conjugates with lost anti-apoptotic activity. These finding highlight potential applications of EGF-nanoparticle conjugates to cancer therapy, as the EGF receptor are highly expressed in cancer cells.

Stem extract of Tabebuia chrysantha induces apoptosis by targeting sEGFR in Ehrlich Ascites Carcinoma

Ethnopharmacological relevanceThe plant Tabebuia chrysantha (Jaq.) Nicholson (Bignoniaceae) is commonly known as “Golden Goddess” in the Southern part of India and “Golden Trumpet Tree “ in Central America. Stems of this plant have been traditionally used for antioxidant, anti-inflammatory, antimicrobial and anticancer actions. Aim of the studyTo evaluate the antitumor activity of methanol extract of Tabebuia chrysantha stem (METC). Materials and methodsThe in vivo antitumor potential of METC against Ehrlich Ascites Carcinoma (EAC) in Swiss albino mice was assessed by evaluating tumor volume, viable and nonviable tumor cell count, tumor weight, hematological parameters, biochemical parameters, and antioxidant parameters. The in vitro antitumor potential of METC at different concentrations (100, 200, 400, 800, 1000) µg/mL has been evaluated, by using the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] and Trypan blue dilution assay for a period of 3 h treatment. Before that, the crude extract was pre-screened for cytotoxicity property using Brine shrimp lethality bioassay. ResultsPhytoconstituents 2-Hydroxynaphthalene-1,4-dione, β-lapachone and 2-((dimethylamino)methyl)-3-methoxynaphthalene-1,4-dione were isolated from the METC. Their occurrence and structures were determined by HPLC chromatography, UV spectroscopy, and 1D and 2D NMR spectroscopies respectively. The extract showed a direct cytotoxic effect on EAC cells in a dose-dependent manner with IG50 value 463.27 µg/mL in MTT assay and 443.58 µg/mL in trypan blue dilution assay. The METC (300 mg/kg) and 5-FU (30 mg/kg) exhibited significant (p < 0.001) decrease in tumor volume, tumor weight and viable cell count of EAC-treated mice. Also, hematological profile, tissue parameters such as lipid peroxidation, reduced glutathione, superoxide dismutase, and catalase were reverted to the normal levels compared to the EAC control group. The Western blotting analysis demonstrated apoptosis of carcinoma was due to inhibition of soluble epidermal growth factor receptor proteins (sEGFR) expression in the blood. ConclusionThe antitumor potential of the stem extract of T chrysantha was due to naphthaquinones and polyphenol content in the crude extract and so T chrysantha could be a cytotoxic plant to control tumor growth.

A Disintegrin and Metalloproteinase Domain-8: A Novel Protective Proteinase in Chronic Obstructive Pulmonary Disease.

ADAM8 (a disintegrin and metalloproteinase domain-8) is expressed by leukocytes and epithelial cells in health, but its contribution to the pathogenesis of chronic obstructive pulmonary disease (COPD) is unknown. To determine whether the expression of ADAM8 is increased in the lungs of patients with COPD and cigarette smoke (CS)-exposed mice, and whether ADAM8 promotes the development of COPD. ADAM8 levels were measured in lung, sputum, plasma, and/or BAL fluid samples from patients with COPD, smokers, and nonsmokers, and wild-type (WT) mice exposed to CS versus air. COPD-like lung pathologies were compared in CS-exposed WT versus Adam8-/- mice. ADAM8 immunostaining was reduced in macrophages, and alveolar and bronchial epithelial cells in the lungs of patients with COPD versus control subjects, and CS- versus air-exposed WT mice. ADAM8 levels were similar in plasma, sputum, and BAL fluid samples from patients with COPD and control subjects. CS-exposed Adam8-/- mice had greater airspace enlargement and airway mucus cell metaplasia than WT mice, but similar small airway fibrosis. CS-exposed Adam8-/- mice had higher lung macrophage counts, oxidative stress levels, and alveolar septal cell death rates, but lower alveolar septal cell proliferation rates and soluble epidermal growth factor receptor BAL fluid levels than WT mice. Adam8 deficiency increased lung inflammation by reducing CS-induced activation of the intrinsic apoptosis pathway in macrophages. Human ADAM8 proteolytically shed the epidermal growth factor receptor from bronchial epithelial cells to reduce mucin expression in vitro. Adam8 bone marrow chimera studies revealed that Adam8 deficiency in leukocytes and lung parenchymal cells contributed to the exaggerated COPD-like disease in Adam8-/- mice. Adam8 deficiency increases CS-induced lung inflammation, emphysema, and airway mucus cell metaplasia. Strategies that increase or prolong ADAM8's expression in the lung may have therapeutic efficacy in COPD.

Contact guidance is cell cycle-dependent.

Cancer cell migration is essential for metastasis, during which cancer cells move through the tumor and reach the blood vessels. In vivo, cancer cells are exposed to contact guidance and chemotactic cues. Depending on the strength of such cues, cells will migrate in a random or directed manner. While similar cues may also stimulate cell proliferation, it is not clear whether cell cycle progression affects migration of cancer cells and whether this effect is different in random versus directed migration. In this study, we tested the effect of cell cycle progression on contact guided migration in 2D and 3D environments, in the breast carcinoma cell line, FUCCI-MDA-MB-231. The results were quantified from live cell microscopy images using the open source lineage editing and validation image analysis tools (LEVER). In 2D, cells were placed inside 10 μm-wide microchannels to stimulate contact guidance, with or without an additional chemotactic gradient of the soluble epidermal growth factor. In 3D, contact guidance was modeled by aligned collagen fibers. In both 2D and 3D, contact guidance was cell cycle-dependent, while the addition of the chemoattractant gradient in 2D increased cell velocity and persistence in directionally migrating cells, regardless of their cell cycle phases. In both 2D and 3D contact guidance, cells in the G1 phase of the cell cycle outperformed cells in the S/G2 phase in terms of migration persistence and instantaneous velocity. These data suggest that in the presence of contact guidance cues in vivo, breast carcinoma cells in the G1 phase of the cell cycle may be more efficient in reaching the neighboring vasculature.

The expression of serum sEGFR, sFlt-1, sEndoglin and PLGF in preeclampsia.

The ratio of sFlt-1/sEGFR could be used as a novel candidate biochemical marker in monitoring the severity of preterm preeclampsia. sEndoglin and sEGFR may be involved in the pathogenesis of SGA in preterm preelampsia.