Vitronectin, fibronectin and epidermal growth factor induce proliferation via the JNK and ERK pathways in insulinoma INS-1 cells

An insulinoma is a tumor formed by beta cells in the Langerhans islets of the pancreas. Vitronectin (VTN), fibronectin (FN) and epidermal growth factor (EGF) are important in cell signaling. The aim of this study was to investigate the molecular mechanism that occurs in INS-1 cells with the administration of VTN, FN and EGF in proliferative doses. We determined the proliferative doses of EGF, VTN and FN. The molecular mechanism of proliferation has been investigated alone or in the combination of these proteins. It was observed that INS-1 cells did not have VTN and FN. Cell viability increased with the administration of 0.1 μg/ml VTN, 0.1 μg/ml FN and 1 mg/ml EGF. Proliferation increased with the administration of FN + EGF, and VTN + FN + EGF together when compared to the control group. The total JNK levels did not change between the groups; however, the active JNK levels increased in the VT + FN + EGF group compared to the control group. The total ERK levels increased in the VT + FN + EGF group, and the active ERK levels increased in the VTN + FN, VTN + EGF and VTN + FN + EGF groups compared to the control group. The JNK and ERK pathways are important for proliferation. The JNK and ERK pathways were activated in VTN + FN + EGF administered group. However, it was observed that the ERK pathway was more active than the JNK pathway.

Establishment and Culture of Patient-Derived Primary Medulloblastoma Cell Lines

Established cell lines have been extensively used in cancer research. They are easy to obtain and expand and are composed of a relatively uniform population of cells. When experimental conditions are kept standard, these cells allow a high reproducibility of experimental findings from independent research groups. However, because these cell lines have been propagated in culture for decades, additional genetic lesions may be acquired leading to modification of their characteristics as compared to the original tumor. Primary cultures represent a valid alternative. Here, we describe standardized protocols to establish medulloblastoma (MB) patient-derived primary cultures from fresh tumor samples. MB primary cells grow as an adherent culture on a laminin coating and can be propagated in vitro for a limited number of passages, therefore reducing the chances to accumulate molecular alterations compared to long-term cultures. Consequently, they better resemble the original tumor both in terms of biological behavior and molecular characteristics. Low-passage MB primary cells can be used as an in vitro model for biochemical studies and functional assays, representing a useful tool to dissect the contribution of molecular pathways to MB pathogenesis. They can also represent a useful screening tool for potential therapeutic agents in preclinical studies.

Sialidase Attenuates Epidermal Growth Factor Response and Abolishes Antiproliferative Effects of Erlotinib in A549Alveolar Epithelial Cells

Erlotinib is a widely used, reversible tyrosine kinase inhibitor (TKI), targeting pro-proliferative signaling of epidermal growth factor receptor (EGFR). The drug is approved for the first-line treatment of patients with metastatic non-small cell lung cancer with EGFR mutations. Extracellular glycans can affect EGFR expression, dimerization, phosphorylation, and EGF binding. In this study we investigated the effects of EGF and erlotinib on the cell cycle of naive and sialidase (alpha-neuraminidase)-pretreated human A549 alveolar epithelial cells. A549 cells were labeled with propidium iodide, and fractions of cells in different phases of cycle were quantified by flow cytometry. We found that neither did desialilation nor EGF, as well as erlotinib treatment, increase the number of damaged cells (subG0/G1 cell fraction), while erlotinib did significantly increase the number of G0/G1 cells and decrease S + G2/M cell fractions. In naive cells, EGF increased proliferating cell numbers by more than 40%, and this effect was blocked by erlotinib. In desialylated cells, however, proliferation was significantly decreased by about 29%, and EGF and erlotinib did not exert significant effects. We conclude that changes in alveolar epithelial cell membrane glycosylation may affect function of growth-promoting receptors and erlotinib effectiveness.

EGF/EGFR upregulates and cooperates with Netrin-4 to protect glioblastoma cells from DNA damage-induced senescence

BACKGROUND

Glioblastoma multiforme (GBM) is the most malignant central nervous system tumor. Alkylating agent, temozolomide (TMZ), is currently the first-line chemotherapeutic agent for GBM. However, the sensitivity of GBM cells to TMZ is affected by many factors. And, several clinic trials, including co-administration of TMZ with other drugs, have failed in successful treatment of GBM. We have previously reported that Netrin-4 (NTN4), a laminin-like axon guidance protein, plays a protective role in GBM cell senescence upon TMZ-triggered DNA damage. However, the master regulator of NTN4 needs further elucidation. Epidermal growth factor/Epidermal growth factor receptor (EGF/EGFR) can modulate the expression of various extracellular matrix related molecules, and prevent DNA damage in GBM cells. In this study, we investigated the relationship between EGF/EGFR signaling and NTN4, and explored their effect on therapeutic efficacy in GBM cells upon TMZ treatment.

METHODS

Co-expression analysis were performed by using the RNA sequencing data from NIH 934 cell lines and from single cell RNA sequencing data of GBM tumor. The co-expressing genes were used for GO enrichment and signaling pathway enrichment. mRNA expression of the target genes were quantified by qPCR, and cell senescence were investigated by Senescence-Associated Beta-Galactosidase Staining. Protein phosphorylation were observed and analyzed by immunoblotting. The RNA sequencing data and clinical information of TMZ treated patients were extracted from TCGA-glioblastoma project, and then used for Kaplan-Meier survival analysis.

RESULTS

Analysis of RNA sequencing data revealed a potential co-expression relationship between NTN4 and EGFR. GO enrichment of EGFR-correlated genes indicated that EGFR regulates GBM cells in a manner similar to that in central nervous system development and neural cell differentiation. Pathway analysis suggested that EGFR and its related genes contribute to cell adhesion, extracellular matrix (ECM) organization and caspase related signaling. We also show that EGF stimulates NTN4 expression in GBM cells and cooperates with NTN4 to attenuate GBM cell senescence induced by DNA damage, possibly via AKT and ERK. Clinical analysis showed that co-expression of EGFR and NTN4 significantly predicts poor survival in TMZ-treated GBM patients.

CONCLUSIONS

This study indicates that EGF/EGFR regulates and cooperates with NTN4 in DNA damage resistance in GBM. Therefore, our findings provide a potential therapeutic target for GBM.

Role of caveolin-1 in epidermal stem cells during burn wound healing in rats

Local transplantation of stem cells has therapeutic effects on skin damage but cannot provide satisfactory wound healing. Studies on the mechanisms underlying the therapeutic effects of stem cells on skin wound healing will be needed. Hence, in the present study, we explored the role of Caveolin-1 in epidermal stem cells (EpiSCs) in the modulation of wound healing. We first isolated EpiSCs from mouse skin tissues and established stable EpiSCs with overexpression of Caveolin-1 using a lentiviral construct. We then evaluated the epidermal growth factor (EGF)-induced cell proliferation ability using cell counting Kit-8 (CCK-8) assay and assessed EpiSC pluripotency by examining Nanog mRNA levels in EpiSCs. Furthermore, we treated mice with skin burn injury using EpiSCs with overexpression of Caveolin-1. Histological examinations were conducted to evaluate re-epithelialization, wound scores, cell proliferation and capillary density in wounds. We found that overexpression of Caveolin-1 in EpiSCs promoted EGF-induced cell proliferation ability and increased wound closure in a mouse model of skin burn injury. Histological evaluation demonstrated that overexpression of Caveolin-1 in EpiSCs promoted re-epithelialization in wounds, enhanced cellularity, and increased vasculature, as well as increased wound scores. Taken together, our results suggested that Caveolin-1 expression in the EpiSCs play a critical role in the regulation of EpiSC proliferation ability and alteration of EpiSC proliferation ability may be an effective approach in promoting EpiSC-based therapy in skin wound healing.

Targeted Drug Delivery Via Human Epidermal Growth Factor Receptor for Sustained Release of Allyl Isothiocyanate

In this study, allyl-isothiocyanate (AITC)-loaded Polylactic-Co-Glycolic Acid (PLGA) Nanoparticles (NPs) were prepared for targeting epithelial squamous carcinoma cells using a specific antibody targeting the Epidermal Growth Factor (EGF) receptor overexpressed on the cell membranes. AITC-loaded PLGA NPs showed more effective anticancer properties compared with free AITC, and their cytotoxicity was even more pronounced when the anti-EGFR antibody was covalently attached to the NPs surface. This targeting ability was additionally tested by co-culturing cervical HeLa cells, with very few EGFR on the membranes, and epithelial squamous carcinoma A431 cells, which largely overexpressed EFGR, being observed the specific localization of the antibody-functionalized AITC-loaded PLGA NPs solely in the latter types of cells, whereas non-functionalized NPs were distributed randomly in both cell types in much lesser extents. Thus, our findings support the development of drug delivery strategies that enhances the delivery of anti-cancer natural compounds to tumor tissue, in this case, by targeting specific tumor cell receptors with cell-specific ligands followed by tumor sensitization.

EGF receptor plays a role in the mechanism of glutamine-mediated prevention of alcohol-induced gut barrier dysfunction and liver injury

Recent study indicated that glutamine prevents alcoholic tissue injury in mouse gut and liver. Here we investigated the potential role of Epidermal Growth Factor Receptor (EGFR) in glutamine-mediated prevention of ethanol-induced colonic barrier dysfunction, endotoxemia and liver damage. Wild-type and EGFR*Tg transgenic (expressing dominant negative EGFR) mice were fed 1-6% ethanol in Lieber-DeCarli diet. Gut permeability was measured by vascular-to-luminal flux of FITC-inulin, and junctional integrity assessed by confocal microscopy. Liver injury was evaluated by plasma transaminases, histopathology and triglyceride analyses. Glutamine effect on acetaldehyde-induced tight junction disruption was investigated in Caco-2 cell monolayers. Doxycycline-induced expression of EGFR* blocked glutamine-mediated prevention of ethanol-induced disruption of colonic epithelial tight junction, mucosal permeability and endotoxemia. Ethanol activated cofilin and disrupted actin cytoskeleton, which was blocked by glutamine in an EGFR-dependent mechanism. Ethanol down-regulated antioxidant gene expression and up-regulated cytokine and chemokine gene expression, which were blocked by glutamine in wild-type mice in the presence or absence of doxycycline, but not in EGFR*Tg mice in the presence of doxycycline. Histopathology, plasma transaminases, triglyceride and expression of chemokine and antioxidant genes indicated ethanol-induced liver damage, which were blocked by glutamine in an EGFR-dependent mechanism. Src kinase activity and extracellular ligand binding domain of EGFR are required for glutamine-mediated protection of barrier function in Caco-2 cell monolayers. Glutamine released metalloproteinases into the medium, and metalloproteinase inhibitors blocked glutamine-mediated protection of barrier function. Results demonstrate that EGFR plays an important role in glutamine-mediated prevention of alcoholic gut permeability, endotoxemia and liver damage.

Pretreatment factors affecting traumatic tympanic membrane regeneration therapy using epidermal growth factor

OBJECTIVE

The use of epidermal growth factor (EGF) to achieve closure of human traumatic tympanic membrane perforations (TMPs) was recently reported. However, pretreatment factors affecting healing outcomes have seldom been discussed. This study was performed to evaluate pretreatment factors contributing to the success or failure of TMP healing using EGF.

DESIGN AND PARTICIPANTS

This was a retrospective cohort study of 95 TMPs who were observed for at least 6 months after EGF treatment. Eleven factors considered likely to affect healing outcome were evaluated by univariate and multivariate logistic regression analyses.

INTERVENTIONS

Each traumatic TMP was treated by daily topical application of EGF. The main outcome measures were complete closure versus failure to close and mean closure time.

RESULTS

A total of 95 patients were included in the analyses. The total closure rate was 92.6% at 6 months, and the mean closure time was 10.5 ± 4.8 days. The closure rate was not significantly different according to the duration of perforation ≤3 days and >3 days (P = 0.816). However, the mean closure time was significantly different according to the duration of perforation (P < 0.001). The perforation size did not affect the closure rate (P = 0.442). The mean closure time in the low-dose EGF group was significantly shorter than that in the high-dose EGF group (P = 0.001). Logistic regression analyses showed that perforations with preexisting myringosclerosis were more likely to fail to close compared to those without preexisting myringosclerosis (P = 0.001). Multivariate logistic regression analyses showed that the duration of perforation (P = 0.011), size of perforation (P < 0.001), and involvement of the malleus in perforation (P = 0.005) were factors independently correlated with closure time.

CONCLUSIONS

Daily application of EGF can be used to treat all traumatic TMPs. The size of the perforation and inverted edges did not affect the closure rate, and the most beneficial dosage was sufficient to keep the eardrum moist. Multivariate logistic regression analyses revealed a significant correlation between preexisting myringosclerosis and failure to heal. Nevertheless, the size of perforation, starting time of application, and malleus injury were independent prognostic factors for prolonged healing time.

CT texture analysis as predictive factor in metastatic lung adenocarcinoma treated with tyrosine kinase inhibitors (TKIs)

PURPOSE

To assess the predictive and prognostic value of pre-treatment CT texture features in lung adenocarcinoma treated with tyrosine kinase inhibitors (TKI).

MATERIALS AND METHODS

Texture analysis was performed using commercially available software (TexRAD Ltd, Cambridge, UK) on pre-treatment contrast-enhanced CT studies from 50 patients with metastatic lung adenocarcinoma treated by TKI. Texture features were quantified on a 5-mm-thick central slice of the primary tumor and were correlated with progression-free and overall survival (PFS and OS) using an internally cross-validated machine learning approach then validated on a bootstrapped sample.

RESULTS

Median PFS and OS were 10.5 and 20.7 months, respectively. A noninvasive signature based on five texture parameters predicted 6-month progression with Area Under the Curve (AUC) of 0.8 (95% CI) and 1-year progression with AUC of 0.76. A high-risk group had hazard ratios for progression of 4.63 and 5.78 when divided by median and best cut-off points, respectively. Texture signature did not correlate with OS. Available clinical variables did not correlate with PFS or with OS.

CONCLUSION

Texture features seem to be associated with PFS in lung adenocarcinoma treated with TKI.

Combined use of bFGF/EGF and all-trans-retinoic acid cooperatively promotes neuronal differentiation and neurite outgrowth in neural stem cells

Neural stem cells (NSCs) as sources of new neurons in brain injuries or diseases are required to not only elicit neurons for neuronal repair, but also to enhance neurite outgrowth for neuronal network reestablishment. Various trophic or chemotropic factors have been shown to cooperatively improve NSC neurogenesis. However, effects of combined treatment of all-trans-retinoic acid (RA) with GF (Basic fibroblast growth factor and epidermal growth factor, bFGF/EGF) on neurogenesis of NSCs are poorly understood. To address this question, NSCs were isolated from the forebrains of embryonic mice, and treated with GF and RA either alone or in combination for differentiation in vitro. Neurons and astrocytes differentiated from NSCs were stained for MAP2 and GFAP separately by immunofluorescence. The results indicated that GF displayed superior efficacy in promoting neuronal differentiation, and RA showed better efficacy in advancing neurite outgrowth by increasing both neurite length and number. In addition, higher differentiation efficiency of neurons to astrocytes in RA or GF, or both acted at the early stage. However, more importantly, compared with RA alone, GF and RA in combination enhanced neuronal differentiation. Moreover, the combined use of GF and RA increased the length and number of neurites compared with GF, as well as the relative expression level of Smurf1. In addition, astrocytes induced by GF, RA, or both exhibited a radial glia-like morphology with long processes differing from serum effects, which might in part attribute to the total numbers of neurons. These findings for the first time unveil the roles of combined use of GF and RA on the neurogenesis of NSCs, suggesting that the use of this combination could be a comprehensive strategy for the functional repair of the nervous system through promoting neuronal differentiation, and advancing neurite outgrowth.

In vitro culture supplementation of EGF for improving the survival of equine preantral follicles

Folliculogenesis is a process of development and maturation of the ovarian follicles, being essential for the maintenance of fertility. In in vivo conditions, 99.9% of the follicles of an ovary do not ovulate and undergo atresia. In order to minimize this loss and to clarify the existing mechanisms, a technique was developed that allows for the in vitro follicular development. The objective of this study was to evaluate the effects of different epidermal growth factor (EGF) concentrations on the in vitro culturing of equine preantral follicles. Ovaries (n = 10) were collected from a local slaughterhouse of mares in seasonal anestrus, washed with 70% alcohol and PBS, and transported. The inner portion of the ovary was divided into 11 fragments of approximately 3 × 3 × 1 mm. A fragment of each ovary was immediately fixed in Bouin (control group). The remaining 10 fragments were individually cultured for 2 and 6 d. The medium was supplemented with different concentrations of EGF (0, 10, 50, 100, and 200 ng/mL). After cultivation, the fragments were processed and classified according to the developmental stage and morphology. In total, 1065 slides containing 6105 tissue sections were evaluated. Within 2 d of culture, there was a higher proportion of intact follicles at the EGF concentrations of 0 and 100 ng/mL (p > 0.05). After 6 d of culture, only the EGF concentration of 100 ng/mL demonstrated a difference when compared to the other treatments (0, 10, 50 and 200 ng/mL of EGF, p > 0.05). There was follicular development after 2 d at all EGF concentrations. Thus, we suggest that EGF promotes follicular survival in equines at a concentration of 100 ng/mL in in vitro cultures of ovarian fragments for 2 d. In addition, we suggest that EGF promotes follicular survival in equines at a concentration of 100 ng/mL in situ cultivation.

Epidermal growth factor can signal via β-catenin to control proliferation of mesenchymal stem cells independently of canonical Wnt signalling

Bone marrow mesenchymal stem/stromal cells (MSCs) maintain bone homeostasis and repair through the ability to expand in response to mitotic stimuli and differentiate into skeletal lineages. Signalling mechanisms that enable precise control of MSC function remain unclear. Here we report that by initially examining differences in signalling pathway expression profiles of individual MSC clones, we identified a previously unrecognised signalling mechanism regulated by epidermal growth factor (EGF) in primary human MSCs. We demonstrate that EGF is able to activate β-catenin, a key component of the canonical Wnt signalling pathway. EGF is able to induce nuclear translocation of β-catenin in human MSCs but does not drive expression of Wnt target genes or T cell factor (TCF) activity in MSC reporter cell lines. Using an efficient Design of Experiments (DoE) statistical analysis, with different combinations and concentrations of EGF and Wnt ligands, we were able to confirm that EGF does not influence the Wnt/β-catenin pathway in MSCs. We show that the effects of EGF on MSCs are temporally regulated to initiate early “classical” EGF signalling mechanisms (e.g via mitogen activated protein kinase) with delayed activation of β-catenin. By RNA-sequencing, we identified gene sets that were exclusively regulated by the EGF/β-catenin pathway, which were distinct from classical EGF-regulated genes. However, subsets of classical EGF gene targets were significantly influenced by EGF/β-catenin activation. These signalling pathways cooperate to enable EGF-mediated proliferation of MSCs by alleviating the suppression of cell cycle pathways induced by classical EGF signalling.

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Epidermal growth factor (EGF) controls mesenchymal stem cell (MSC) proliferation.

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EGF signals through β-catenin in MSCs but not in related fibroblastic cells.

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Classical EGF and EGF/β-catenin cooperatively regulate distinct gene sets in MSCs.

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EGF/β-catenin enables MSC proliferation by alleviating cell cycle suppression.

HCV modifies EGF signalling and upregulates production of CXCR2 ligands: Role in inflammation and antiviral immune response

BACKGROUND & AIMS

To affect immune response and inflammation, the hepatitis C virus (HCV) substantially influences intercellular communication pathways that are decisive for immune cell recruitment. The present study investigates mechanisms by which HCV modulates chemokine-mediated intercellular communication from infected cells.

METHODS

Chemokine expression was studied in HCV_cc-infected cell lines or cell lines harbouring a subgenomic replicon, as well as in serum samples from patients. Expression or activity of mediators and signalling intermediates was manipulated using knockdown approaches or specific inhibitors.

RESULTS

HCV enhances expression of CXCR2 ligands in its host cell via the induction of epidermal growth factor (EGF) production. Knockdown of EGF or of the p65 subunit of the NF-κB complex results in a substantial downregulation of HCV-induced CXCR2 ligand expression, supporting the involvement of an EGF-dependent mechanism as well as activation of NF-κB. Furthermore, HCV upregulates expression of CXCR2 ligands in response to EGF stimulation via downregulation of the T-cell protein tyrosine phosphatase (TC-PTP [PTPN2]), activation of NF-κB, and enhancement of EGF-inducible signal transduction via MEK1 (MAP2K1). This results in the production of a cytokine/chemokine pattern by the HCV-infected cell that can recruit neutrophils but not monocytes.

CONCLUSIONS

These data reveal a novel EGF-dependent mechanism by which HCV influences chemokine-mediated intercellular communication. We propose that this mechanism contributes to modulation of the HCV-induced inflammation and the antiviral immune response.

LAY SUMMARY

In most cases hepatitis C virus (HCV) results in chronic infection and persistent viral replication, taking decades until development of overt disease. To achieve such a course, the respective virus must have developed mechanisms to circumvent antiviral response, to modulate the inflammatory response and to utilise the infrastructure of its host with moderate effect on its viability. The present study provides novel data indicating that HCV induces epidermal growth factor production in its host cell, enhancing epidermal growth factor-inducible expression of chemokines that bind to the CXCR2 receptor and recruit neutrophile granulocytes. Importantly, chemokines are critical mediators determining the pattern of immune cells recruited to the site of injury and thereby the local inflammatory and immunological milieu. These data strongly suggest that HCV triggers mechanisms that enable the virus to influence the inflammatory and immunological processes of its host.

A new nanoscale transdermal drug delivery system: oil body-linked oleosin-hEGF improves skin regeneration to accelerate wound healing

Background

Epidermal growth factor (EGF) can promote cell proliferation as well as migration, which is feasible in tissue wound healing. Oil bodies have been exploited as an important platform to produce exogenous proteins. The exogenous proteins were expressed in oil bodies from plant seeds. The process can reduce purification steps, thereby significantly reducing the purification cost. Mostly, the diameter of oil body particle ranges between 1.0 and 1.5 µm in the safflower seeds, however, it reduces to 700–1000 nm in the transgenic safflower seeds. The significant reduction of particle size in transgenic seeds is extremely beneficial to skin absorption.

Results

The diameter of oil body in the transgenic safflower seeds was recorded in the range of 700–1000 nm. The smaller particle size improved their skin absorption. The expression level of oleosin-hEGF-hEGF in T3 transgenic seeds was highest at 69.32 mg/g of seeds. The oil body expressing oleosin-hEGF-hEGF had significant proliferative activity on NIH/3T3 cells and improved skin regeneration thereby accelerating wound healing in rats. The wound coverage rate exceeded 98% after treatment for 14 days with oil body expressing oleosin-hEGF-hEGF, while the saline without EGF group and wild type oil body group both showed less than 80%. The neonatal fibroblast and collagen were found to be increased in the safflower oil body expressing oleosin-hEGF-hEGF treatment group. TGF-β1, bFGF and VEGF were noted as important growth factors in the repair of cutaneous wounds. Their expression level increased after 4 and 7 day treatment, but decreased after 14 days. Therefore, it can promote skin regeneration to accelerate wounds healing.

Conclusions

The expression of oleosin-hEGF-hEGF in T3 transgenic seeds was 80.43 ng/μL oil body. It had significant proliferative activity on NIH/3T3 cells and improved skin regeneration to accelerate wound healing in rats. The expression process of TGF-β1, bFGF and VEGF increased at first and then gradually declined.

Electronic supplementary material

The online version of this article (10.1186/s12951-018-0387-5) contains supplementary material, which is available to authorized users.

Reversible secretome and signaling defects in diabetic mesenchymal stem cells from peripheral arterial disease patients

OBJECTIVE

Regenerative medicine seeks to stall or to reverse the pathologic consequences of chronic diseases. Many people with diabetes have peripheral arterial disease (PAD), which increases their already high risk of major amputation. Cellular therapies are a promising regenerative medicine approach to PAD that can be used to focally inject regenerative cells to endangered tissue beds. Mesenchymal stem cells (MSCs) are known to promote tissue regeneration through stromal support and paracrine stimulation of new blood vessels (angiogenesis). Whereas little is known about human diabetic MSCs (dMSCs), particularly those from patients with PAD, dMSCs have a limited expansion capacity but can be improved with human platelet lysate (PL) supplementation. PL is rich in many growth factors, including epidermal growth factor (EGF), which is known to be important to cell proliferation and survival signaling pathways. We hypothesize that dMSCs have a reversible defect in EGF receptor pathways. The objective of this work was to test this hypothesis using dMSCs from PAD patients.

METHODS

The secretome expression of EGF and prominent angiogens was characterized from bone marrow (BM)-derived and adipose tissue-derived (ATD) dMSCs from five patients (six limbs) undergoing major amputation. Western blot was used to characterize the AKT and extracellular signal-regulated protein kinases 1 and 2 expression in dMSCs under standard culture (5% fetal bovine serum plus fibroblast growth factor 2 [FGF2]), 5% human PL, or 5% fetal bovine serum plus EGF. Healthy donor MSCs were control cells. The angiogenic activity of BM- and ATD-dMSCs was tested on human umbilical vein endothelial cells (ECs). Paired t-test, analysis of variance, and Kruskal-Wallis tests were used as appropriate.

RESULTS

Both BM- and ATD-dMSCs had typical MSC surface marker expression and similar expansion profiles, and they did not express EGF in their secretome. PL supplementation of dMSCs improved AKT signaling, but they were resistant to FGF2 activation of extracellular signal-regulated protein kinases 1 and 2. EGF supplementation led to similar AKT expression as with PL, but PL had greater phosphorylation of AKT at 30 and 60 minutes. The conditioned media from both BM- and ATD-dMSCs had robust levels of prominent angiogens (vascular endothelial growth factor, monocyte chemoattractant protein 1, hepatocyte growth factor), which stimulated EC proliferation and migration, and the co-culture of dMSCs with ECs led to significantly longer EC sprouts in three-dimensional gel than EC-alone pellets.

CONCLUSIONS

PL and EGF supplementation improves AKT expression in dMSCs over that of FGF2, but PL improved pAKT over that of EGF. Thus, PL supplementation strategies may improve AKT signaling, which could be important to MSC survival in cellular therapies. Furthermore, BM- and ATD-dMSCs have similar secretomes and robust in vitro angiogenic activity, which supports pursuing dMSCs from both reservoirs in regenerative medicine strategies.

Astragaloside VI Promotes Neural Stem Cell Proliferation and Enhances Neurological Function Recovery in Transient Cerebral Ischemic Injury via Activating EGFR/MAPK Signaling Cascades

Radix Astragali (AR) is a commonly used medicinal herb for post-stroke disability in Traditional Chinese Medicine but its active compounds for promoting neurogenic effects are largely unknown. In the present study, we tested the hypothesis that Astragaloside VI could be a promising active compound from AR for adult neurogenesis and brain repair via targeting epidermal growth factor (EGF)-mediated MAPK signaling pathway in post-stroke treatment. By using cultured neural stem cells (NSCs) and experimental stroke rat model, we investigated the effects of Astragaloside VI on inducing NSCs proliferation and self-renewal in vitro, and enhancing neurogenesis for the recovery of the neurological functions in post-ischemic brains in vivo. For animal experiments, rats were undergone 1.5 h middle cerebral artery occlusion (MCAO) plus 7 days reperfusion. Astragaloside VI (2 μg/kg) was daily administrated by intravenous injection (i.v.) for 7 days. Astragaloside VI treatment promoted neurogenesis and astrogenic formation in dentate gyrus zone, subventricular zone, and cortex of the transient ischemic rat brains in vivo. Astragaloside VI treatment enhanced NSCs self-renewal and proliferation in the cultured NSCs in vitro without affecting NSCs differentiation. Western blot analysis showed that Astragaloside VI up-regulated the expression of nestin, p-EGFR and p-MAPK, and increased neurosphere sizes, whose effects were abolished by the co-treatment of EGF receptor inhibitor gefitinib and ERK inhibitor PD98059. Behavior tests revealed that Astragaloside VI promoted the spatial learning and memory and improved the impaired motor function in transient cerebral ischemic rats. Taken together, Astragaloside VI could effectively activate EGFR/MAPK signaling cascades, promote NSCs proliferation and neurogenesis in transient cerebral ischemic brains, and improve the repair of neurological functions in post-ischemic stroke rats. Astragaloside VI could be a new therapeutic drug candidate for post-stroke treatment.

Topical epidermal growth factor spray for the treatment of chronic diabetic foot ulcers: A phase III multicenter, double-blind, randomized, placebo-controlled trial

AIMS

This study was conducted to evaluate the efficacy and safety of a novel spray-applied growth factor therapy containing recombinant human epidermal growth factor (rhEGF) for the treatment of chronic diabetic foot ulcers (DFU).

METHODS

This study was a phase III double-blind, randomized, placebo-controlled trial. 167 adult patients at six medical centers were randomized to receive routine wound care plus either topical spray treatment with 0.005% rhEGF (n = 82) or an equivalent volume of saline spray (n = 85) twice a day until ulcer healing or for up to 12 weeks.

RESULTS

Demographics, medical status, and wound characteristics were comparable between rhEGF and placebo groups. More patients in the rhEGF group significantly had complete wound healing compared to placebo (73.2% versus 50.6%, respectively; P = .001). Wound healing velocity was faster in the rhEGF group (P = .029) regardless of HbA1c levels. The rhEGF group had a shorter median time to 50% ulcer size reduction (21 versus 35 days; hazard ratio = 3.13, P < .001) and shorter time to complete ulcer healing (56 versus 84 days; hazard ratio = 2.13, P < .001).

CONCLUSIONS

This study confirms that application of spray-applied rhEGF in DFU patients results in faster healing velocity and higher complete healing rate regardless of HbA1c levels.

[Meta analysis on effectiveness of epidermal growth factor in treating patients with inhalation injury]

Objective: To systematically evaluate the effectiveness of epidermal growth factor (EGF) in treating patients with inhalation injury by meta analysis. Methods: Databases including PubMed, Cochrance Library, and Embase were searched using key words " inhalation injury, smoke inhalation injury, epidermal growth factor, and EGF" , and Chinese Journals Full-text Database, China Biology Medicine disc, VIP Database, and Wanfang Database were searched using key words in Chinese version "," to obtain the randomized controlled trails about EGF published publicly in the treatment of patients with inhalation injury from the establishment of each database to December 2017. The measurement indexes included content of total protein and albumin, colloid osmotic pressure (COP), the number of total cells, percentages of neutrophils, lymphocytes, and fibroblasts in bronchoalveolar lavage fluid (BALF), the time of disappearance of pulmonary symptoms, the time of exfoliation of necrotic mucous membrane, the time of removal of tracheal tube, the amount of respiratory secretions, and the incidence of lung infection. Meta-analysis was conducted by RevMan 5.3 statistical software. Results: A total of 6 trials involving 375 patients were included, with 182 patients in group EGF who received EGF treatment and 173 patients in conventional treatment group who received conventional treatment. All of the 6 trails had unclear risk of bias. The content of total protein and albumin and COP in BALF of patients in group EGF were lower than those in conventional treatment group, with standardized mean differences (SMDs) respectively -9.37, -26.77 , and -8.13 [with 95% confidence intervals (CIs) respectively -14.11--4.63, -41.85--11.69, -9.54--6.73, P<0.001]. The number of total cells and percentages of neutrophils and lymphocytes in BALF of patients in group EGF were lower than those in conventional treatment group, while the percentage of fibroblasts in BALF of patients in group EGF was higher than that in conventional treatment group, with SMDs respectively -20.22, -13.08, -12.28, 2.99 (with 95% CIs respectively -22.27--17.66 , -14.76--11.40, -13.86--10.70, 2.48-3.50, P<0.001). The time of disappearance of pulmonary symptoms, the time of exfoliation of necrotic mucous membrane, and the time of removal of tracheal tube of patients in group EGF were shorter than those in conventional treatment group, with SMDs respectively -1.05, -1.22 , -1.11 (with 95% CIs respectively -1.36--0.74, -1.54--0.91, -1.39--0.82, P<0.001). The amount of respiratory secretions of patients in group EGF was lower than that in conventional treatment group, with SMD -1.44 (with 95% CI -1.90--0.98, P<0.001). The incidence rate of pulmonary infection of patients in group EGF was lower than that in conventional treatment group, with relative risk 0.46 (with 95% CI 0.24-0.89, P<0.05). There may be publication bias in the content of total protein, albumin, and COP in BALF (P<0.05), while the time of disappearance of pulmonary symptoms, the time of exfoliation of necrotic mucous membrane, and the time of removal of tracheal tube showed no significant publication bias (P>0.05). Conclusions: Conventional treatment combined with EGF therapy can reduce respiratory inflammation of inhalation injury, promote restoration of respiratory epithelium, shorten the time of removal of tracheal tube, reduce the incidence of pulmonary infection of patients, and therefore has good effect on inhalation injury.

Production of amphiregulin and recovery from influenza is greater in males than females

Background

Amphiregulin (AREG) is an epidermal growth factor that is a significant mediator of tissue repair at mucosal sites, including in the lungs during influenza A virus (IAV) infection. Previous research illustrates that males of reproductive ages experience less severe disease and recover faster than females following infection with IAV.

Methods

Whether males and females differentially produce and utilize AREG for pulmonary repair after IAV infection was investigated using murine models on a C57BL/6 background and primary mouse and human epithelial cell culture systems.

Results

Following sublethal infection with 2009 H1N1 IAV, adult female mice experienced greater morbidity and pulmonary inflammation during the acute phase of infection as well as worse pulmonary function during the recovery phase of infection than males, despite having similar virus clearance kinetics. As compared with females, AREG expression was greater in the lungs of male mice as well as in primary respiratory epithelial cells derived from mouse and human male donors, in response to H1N1 IAVs. Internalization of the epidermal growth factor receptor (EGFR) was also greater in respiratory epithelial cells derived from male than female mice. IAV infection of Areg knock-out (Areg^−/−) mice eliminated sex differences in IAV pathogenesis, with a more significant role for AREG in infection of male compared to female mice. Deletion of Areg had no effect on virus replication kinetics in either sex. Gonadectomy and treatment of either wild-type or Areg^−/− males with testosterone improved the outcome of IAV as compared with their placebo-treated conspecifics.

Conclusions

Taken together, these data show that elevated levels of testosterone and AREG, either independently or in combination, improve resilience (i.e., repair and recovery of damaged tissue) and contribute to better influenza outcomes in males compared with females.

Value of urinary levels of interleukin-6, epidermal growth factor, monocyte chemoattractant protein type1 and transforming growth factor β1 in predicting the extent of fibrosis lesions in kidney biopsies of patients with IgA nephropathy

OBJECTIVE

To analyse the associations between urinary levels of IL-6 EGF, MCP-1 and TGFβ1 and clinical, biochemical and histopathological characteristics in patients with primary IgA nephropathy and their ability to predict the extent of lesions of glomerular and/or interstitial sclerosis.

PATIENTS AND METHODS

A total of 58 patients with IgA nephropathy were studied. We determined the urine levels of IL-6, EGF, MCP-1, and TGFβ1 at the time of diagnosis. The extent of glomerular and interstitial fibrosis was analyzed by quantitative morphometry and kidney biopsies were classified according to the Oxford criteria. We analysed the ability of these molecules to predict the extent of glomerular and interstitial fibrosis lesions.

RESULTS

IL-6, TGFβ1 and MCP-1 were associated with focal glomerulosclerosis and interstitial fibrosis extension but not with the presence of mesangial, extracapillary or endocapillary proliferation. EGF showed a negative association with interstitial fibrosis. By categorising patients according to the Oxford classification, patients with T1 and T2 scores had significantly higher levels of IL-6, MCP-1, TGF-β1 and significantly lower levels of EGF than patients with T0 scores. By multiple regression and logistic regression analyses, the levels of MCP-1, IL-6 and EGF were independent predictors of the fibrosis surface, after adjusting for age and eGFR.

CONCLUSION

The urinary concentration of IL-6, EGF and MCP-1 provides additional information that significantly improves the estimation of the surface of interstitial fibrosis in patients with IgA nephropathy.

Egr-1 Maintains NSC Proliferation and Its Overexpression Counteracts Cell Cycle Exit Triggered by the Withdrawal of Epidermal Growth Factor

In adult mammals, neural stem cells (NSCs) reside in specialized niches at the level of selected CNS regions, such as the subventricular zone (SVZ). The signaling pathways that reg-ulate NSC proliferation and differentiation remain poorly understood. Early growth response protein 1 (Egr-1) is an important transcription factor, widely studied in the adult mammalian brain, mediating the activation of target genes by a variety of extracellular stimuli. In our study, we aimed at testing how Egr-1 regulates adult NSCs derived from mouse SVZ and, in particular, the interplay between Egr-1 and the proliferative factor EGF. We demonstrate that Egr-1 expression in NSCs is induced by growth factor stimulation, and its level decreases after EGF deprivation or by using AG1478, an inhibitor of the EGF/EGFR signaling pathway. We also show that Egr-1 overexpression rescues the cell proliferation decrease observed either after EGF removal or upon treatment with AG1478, suggesting that Egr-1 works downstream of the EGF pathway. To better understand this mechanism, we investigated targets downstream of both the EGF pathway and Egr-1, and found that they regulate genes involved in NSC proliferation, such as cell cycle regulators, cyclins, and cyclin-dependent kinase inhibitors.

Cost-effectiveness analysis of the human recombinant epidermal growth factor in the management of patients with diabetic foot ulcers

Introduction: Diabetic foot ulcers are one of the most frequent complications of diabetes; such ulcers cause an increase in the costs of the health care of the diabetic patient and can even cause disability due to amputation in the patient. Although a proportion of patients achieve a spontaneous closure of ulcers, others require medical or surgical treatment. Objective: To determine the cost-effectiveness of the intra- and perilesional application of recombinant human epidermal growth factor (rhEGF), as opposed to conventional therapy for the management of patients diagnosed with Wagner's 3 or 4 diabetic foot ulcer in Colombia. Methodology: Using a Markov model, the process of care of a diabetic patient with diagnosis of Wagner's 3 or 4 ulcer receiving conventional treatment, or intra- and perilesional rhEGF, is configured. The evaluation cycles of the treatments are weekly over a 5-year horizon and the outcomes evaluated are quality-adjusted life years (QALYs) and the number of amputations avoided by each treatment scheme, in addition to the total costs for treatments. Results: For the analysed base case, in the outcome of amputations, it was found that the factor presents 39 fewer amputations, in a cohort of 100 patients, compared with conventional treatment. Likewise, QALYs are 0.65 more with the use of rhEGF in an average patient. The estimated cost-utility ratio for the base case would be below the threshold established for Colombia. Conclusions: The intra- and perilesional application of rhEGF is a more effective therapeutic option than conventional therapy in the treatment of patients with Wagner's 3 or 4 diabetic foot ulcers and is cost-effective, taking as an outcome the QALYs for Colombia from the perspective of the health system.

Epidermal growth factor regulates apoptosis and oxidative stress in a rat model of spinal cord injury

Spinal cord injury (SCI) leads to vascular damage and disruption of blood-spinal cord barrier which participates in secondary nerve injury. Epidermal growth factor (EGF) is an endogenous protein which regulates cell proliferation, growth and differention. Previous studies reported that EGF exerts neuroprotective effect in spinal cord after SCI. However, the molecular mechanisms underlying EGF-mediated protection in different regions of nervous system have not shown yet. In this study, we aimed to examine possible anti-apoptotic and protective roles of EGF not only in spinal cord but also in brain following SCI. Twenty-eight adult rats were divided into four groups of seven animals each as follows: sham, trauma (SCI), SCI + EGF and SCI + methylprednisolone (MP) groups. The functional neurological deficits due to the SCI were assessed by behavioral analysis using the Basso, Beattie and Bresnahan (BBB) open-field locomotor test. The alterations in pro-/anti-apoptotic protein levels and antioxidant enzyme activities were measured in spinal cord and frontal cortex. In our study, EGF promoted locomotor recovery and motor neuron survival of SCI rats. EGF treatment significantly decreased Bax and increased Bcl-2 protein expressions both in spinal cord and brain when compared to SCI group. Moreover, antioxidant enzyme activities including catalase, superoxide dismutase (SOD) and glutathione peroxidase (GPx) were increased following EGF treatment similar to MP treatment. Our experiment also suggests that alteration of the ratio of Bcl-2 to Bax may result from decreased apoptosis following EGF treatment. As a conclusion, these results show, for the first time, that administration of EGF exerts its protection via regulating apoptotic and oxidative pathways in response to spinal cord injury in different regions of central nervous system.

A Randomized Phase II Open-Label Multi-Institution Study of the Combination of Bevacizumab and Erlotinib Compared to Sorafenib in the First-Line Treatment of Patients with Advanced Hepatocellular Carcinoma

OBJECTIVES

To investigate the clinical efficacy and tolerability of the combination of bevacizumab (B) and erlotinib (E) compared to sorafenib (S) as first-line treatment for patients with advanced hepatocellular carcinoma (HCC).

METHODS

A total of 90 patients with advanced HCC, Child-Pugh class A-B7 cirrhosis, and no prior systemic therapy were randomly assigned (1: 1) to receive either 10 mg/kg B intravenously every 14 days and 150 mg E orally daily (n = 47) (B+E) or 400 mg S orally twice daily (n = 43). The primary endpoint was overall survival (OS). Secondary endpoints included event-free survival (EFS), objective response rate based on Response Evaluation Criteria in Solid Tumors (RECIST 1.1), time to progression, and safety and tolerability.

RESULTS

The median OS was 8.55 months (95% CI: 7.00-13.9) for patients treated with B+E and 8.55 months (95% CI: 5.69-12.2) for patients receiving S. The hazard ratio (HR) for OS was 0.92 (95% CI: 0.57-1.47). The median EFS was 4.37 months (95% CI: 2.99-7.36) for patients receiving B+E and 2.76 months (95% CI: 1.84-4.80) for patients receiving S. The HR for EFS was 0.67 (95% CI: 0.42-1.07; p = 0.09), favoring B+E over S. When OS was assessed among patients who were Child-Pugh class A, the median OS was 11.4 months (95% CI: 7.5-15.7) for patients treated with B+E (n = 39) and 10.26 months (95% CI: 5.9-13.0) for patients treated with S (n = 38) (HR = 0.88; 95% CI: 0.53-1.46).

CONCLUSIONS

There was no difference in efficacy between the B+E and S arms, although the safety and tolerability profile tended to favor B+E over S based on competing risk analysis.

Deterioration in saliva quality in patients with Sjögren's syndrome: impact of decrease in salivary epidermal growth factor on the severity of intraoral manifestations

Background

Sjögren’s syndrome (SS) is a chronic inflammatory autoimmune disease characterized by lymphocytic infiltration of the exocrine glands, especially the salivary and lacrimal glands. As a result of salivary gland dysfunction, most patients with SS have xerostomia related to a reduced salivary flow rate. In addition to the discomfort due to xerostomia, dry mouth can cause various intraoral manifestations such as refractory stomatitis, ulcer, and atrophic changes in the oral mucosa and tongue, and the patient’s quality of life (QoL) is severely impaired. These manifestations are believed to be caused mainly by a decrease in the clearance in the oral cavity owing to hyposalivation. However, because saliva has several beneficial physiological effects on the intraoral environment, qualitative changes in sialochemistry should also be considered a cause of the refractory intraoral manifestations in SS.

Main text

Salivary epidermal growth factor (EGF) is considered an important cytoprotective factor against injuries. It contributes to wound healing in the oral cavity and to maintenance of mucosal integrity in the oral cavity and gastrointestinal tract. We evaluated changes in salivary EGF levels and assessed the association between salivary EGF levels and the severity of intraoral manifestations in patients with SS. The following novel findings were obtained: (1) salivary EGF levels in SS patients were significantly lower than those in non-SS patients; (2) salivary EGF levels as well as the salivary flow rate decreased with the progression of SS; (3) with prolonged SS disease duration, salivary EGF levels decreased more rapidly than the salivary flow rate; and (4) decreases in salivary EGF levels significantly correlated with exacerbation of the oral health-related QoL in patients with SS.

Conclusions

The deterioration in saliva quality as well as lower intraoral clearance by hyposalivation could play a role in the pathogenesis of refractory intraoral manifestations in patients with SS. Our findings suggest a new target for therapeutic intervention for SS.