Human Inflammatory Neutrophils Express Genes Encoding Peptidase Inhibitors: Production of Elafin Mediated by NF-κB and CCAAT/Enhancer-Binding Protein ß.

The concept of plasticity of neutrophils is highlighted by studies showing their ability to transdifferentiate into APCs. In this regard, transdifferentiated neutrophils were found at inflammatory sites of autoimmune arthritis (AIA). Exposure of neutrophils to inflammatory stimuli prolongs their survival, thereby favoring the acquisition of pathophysiologically relevant phenotypes and functions. By using microarrays, quantitative RT-PCR, and ELISAs, we showed that long-lived (LL) neutrophils obtained after 48 h of culture in the presence of GM-CSF, TNF, and IL-4 differentially expressed genes related to apoptosis, MHC class II, immune response, and inflammation. The expression of anti-inflammatory genes mainly of peptidase inhibitor families is upregulated in LL neutrophils. Among these, the PI3 gene encoding elafin was the most highly expressed. The de novo production of elafin by LL neutrophils depended on a synergism between GM-CSF and TNF via the activation and cooperativity of C/EBPß and NF-κB pathways, respectively. Elafin concentrations were higher in synovial fluids (SF) of patients with AIA than in SF of osteoarthritis. SF neutrophils produced more elafin than blood counterparts. These results are discussed with respect to implications of neutrophils in chronic inflammation and the potential influence of elafin in AIA.

Endogenous Retroviral Elements Generate Pathologic Neutrophils in Pulmonary Arterial Hypertension.

Rationale: The role of neutrophils and their extracellular vesicles (EVs) in the pathogenesis of pulmonary arterial hypertension is unclear. Objectives: To relate functional abnormalities in pulmonary arterial hypertension neutrophils and their EVs to mechanisms uncovered by proteomic and transcriptomic profiling. Methods: Production of elastase, release of extracellular traps, adhesion, and migration were assessed in neutrophils from patients with pulmonary arterial hypertension and control subjects. Proteomic analyses were applied to explain functional perturbations, and transcriptomic data were used to find underlying mechanisms. CD66b-specific neutrophil EVs were isolated from plasma of patients with pulmonary arterial hypertension, and we determined whether they produce pulmonary hypertension in mice. Measurements and Main Results: Neutrophils from patients with pulmonary arterial hypertension produce and release increased neutrophil elastase, associated with enhanced extracellular traps. They exhibit reduced migration and increased adhesion attributed to elevated ß1-integrin and vinculin identified by proteomic analysis and previously linked to an antiviral response. This was substantiated by a transcriptomic IFN signature that we related to an increase in human endogenous retrovirus K envelope protein. Transfection of human endogenous retrovirus K envelope in a neutrophil cell line (HL-60) increases neutrophil elastase and IFN genes, whereas vinculin is increased by human endogenous retrovirus K deoxyuridine triphosphate diphosphatase that is elevated in patient plasma. Neutrophil EVs from patient plasma contain increased neutrophil elastase and human endogenous retrovirus K envelope and induce pulmonary hypertension in mice, mitigated by elafin, an elastase inhibitor. Conclusions: Elevated human endogenous retroviral elements and elastase link a neutrophil innate immune response to pulmonary arterial hypertension.

Eugenol-piperine loaded polyhydroxy butyrate/polyethylene glycol nanocomposite-induced apoptosis and cell death in nasopharyngeal cancer (C666-1) cells through the inhibition of the PI3K/AKT/mTOR signaling pathway.

Nasopharyngeal cancer is a malignancy developing from the nasopharynx epithelium due to smoking and nitrosamine-containing foods. Nasopharyngeal cancer is highly endemic to Southeast Asia. Eugenol and piperine have shown many anticancer activities on numerous cancer types, like colon, lung, liver, and breast cancer. In this study, we amalgamated eugenol and piperine loaded with a polyhydroxy butyrate/polyethylene glycol nanocomposite (Eu-Pi/PHB-PEG-NC) for better anticancer results against nasopharyngeal cancer (C666-1) cells. In the current study, nasopharyngeal cancer cell lines C666-1 were utilized to appraise the cytotoxic potential of Eug-Pip-PEG-NC on cell propagation, programmed cell death, and relocation. Eu-Pi/PHB-PEG-NC inhibits cellular proliferation on C666-1 cells in a dose-dependent manner, and when compared with 20 µg/ml, 15 µg/ml of loaded mixture evidently restrained the passage aptitude of C666-1 cells, this was attended with a downregulated expression of mitochondrial membrane potential. Treatment with 15 µg/ml Eu-Pi/PHB-PEG-NC suggestively amplified cell apoptosis in the C666-1 cells. Furthermore, its cleaved caspase-3, 8, and 9 and Bax gene expression was augmented and Bcl-2 gene expression was diminished after Eu-Pi/PHB-PEG-NC treatment. Additionally, our data established that the collective effect of Eu-Pi/PHB-PEG-NC loaded micelles inhibited the expansion of C666-1 cells augmented apoptosis connected with the intrusion of PI3K/Akt/mTOR signaling pathway.

A High-throughput Bead-based Affinity Assay Enables Analysis of Genital Protein Signatures in Women At Risk of HIV Infection.

Women at high risk of HIV infection, including sex workers and those with active genital inflammation, have molecular signatures of immune activation and epithelial barrier remodeling in samples of their genital mucosa. These alterations in the local immunological milieu are likely to impact HIV susceptibility. We here analyze host genital protein signatures in HIV uninfected women, with high frequency of condom use, living in HIV-serodiscordant relationships. Cervicovaginal secretions from women living in HIV-serodiscordant relationships (n = 62) were collected at three time points over 12 months. Women living in HIV-negative seroconcordant relationships (controls, n = 25) were sampled at one time point. All study subjects were examined for demographic parameters associated with susceptibility to HIV infection. The cervicovaginal samples were analyzed using a high-throughput bead-based affinity assay. Proteins involved in epithelial barrier function and inflammation were increased in HIV-serodiscordant women. By combining several methods of analysis, a total of five proteins (CAPG, KLK10, SPRR3, elafin/PI3, CSTB) were consistently associated with this study group. Proteins analyzed using the affinity set-up were further validated by label-free tandem mass spectrometry in a partially overlapping cohort with concordant results. Women living in HIV-serodiscordant relationships thus had elevated levels of proteins involved in epithelial barrier function and inflammation despite low prevalence of sexually transmitted infections and a high frequency of safe sex practices. The identified proteins are important markers to follow during assessment of mucosal HIV susceptibility factors and a high-throughput bead-based affinity set-up could be a suitable method for such evaluation.

USP18 promotes cell proliferation and suppressed apoptosis in cervical cancer cells via activating AKT signaling pathway.

BACKGROUND: The deubiquitinating (DUB) enzyme ubiquitin-specific protease 18 (USP18), also known as UBP43, is an ubiquitin-specific protease linked to several human malignancies. However, USP18's underlying function in human cervical cancer remains unclear. In the current study, we aimed to analyse the role of USP18 and its signalling pathways in cervical cancer. METHODS: Quantitative real-time polymerase chain reaction (qRT-PCR) and immunohistochemical staining were performed to analyse USP18 levels in cervical cancer and matched to adjacent normal tissues. Moreover, RNA interference (RNAi) and lentiviral-mediated vector transfections were performed to silence and overexpress USP18, respectively, in cervical cancer cells. Further, Cell Counting Kit-8 (CCK-8) and Annexin V/PI staining assays were used to assess its biological function in cell proliferation and apoptosis, respectively. A xenograft model was used to examine USP18's function in vivo. RESULTS: The present findings demonstrated that USP18 was overexpressed in cervical cancer specimens and cell lines. Silencing USP18 in SiHa and Caski cervical cancer cell lines inhibited cell proliferation, induced apoptosis, and promoted cleaved caspase-3 expression. In contrast, USP18 overexpression showed the opposite effects in human HcerEpic cells. A Gene Set Enrichment Analysis revealed that USP18 was enriched in the PI3K/AKT signalling pathway in cervical cancer. Hence, the PI3K/AKT inhibitor LY294002 was used to determine the relationship between USP18 and AKT in cervical cancer cells. Importantly, LY294002 significantly abolished the effects of USP18 overexpression in cervical cancer cells. In vivo, USP18 silencing inhibited human cervical cancer cells' tumorigenicity. CONCLUSIONS: The current study indicates that USP18 is an oncogenic gene in cervical cancer. Our findings not only deepened the understanding of USP18's biological function in cervical cancer pathogenesis, but we also provided novel insight for cervical cancer therapy. TRIAL REGISTRATION: Retrospectively registered.

Expression of serine protease inhibitors in epidermal keratinocytes is increased by calcium but not 1,25-dihydroxyvitamin D3 or retinoic acid.

BACKGROUND: In human skin, the serine proteases kallikrein-related peptidase (KLK)5 and KLK7 degrade corneodesmosome proteins, leading to desquamation. Serine protease activity of the skin is tightly regulated by the interplay between such proteases and serine protease inhibitors, including lymphoepithelial Kazal-type related inhibitor (LEKTI), encoded by SPINK5; secretory leucocyte peptidase inhibitor (SLPI); and elafin. Expression of KLK5 and KLK7 is controlled and upregulated by stimulants such as calcium, 1,25-dihydroxyvitamin D3 [1,25(OH)2 VD3 ] and retinoic acid (RA). OBJECTIVES: To understand the effect of calcium, 1,25(OH)2 VD3 and RA on the expression of serine protease inhibitors in epidermal keratinocytes. METHODS: We stimulated normal human epidermal keratinocytes (NHEKs) with high calcium, 1,25(OH)2 VD3 or RA, and then analysed the expression of serine protease inhibitors using quantitative real-time polymerase chain reaction, enzyme-linked immunosorbent assay and immunocytofluorescence. We also analysed trypsin- and chymotrypsin-like serine protease activities in stimulated NHEKs. RESULTS: High calcium, but not 1,25(OH)2 VD3 or RA, significantly induced the expression of LEKTI, SLPI and elafin at both transcript and protein levels in NHEKs. These inductions were time- and dose-dependent. The activities of trypsin- and chymotrypsin-like serine proteases were significantly up- and downregulated by high calcium, respectively, in NHEKs. CONCLUSIONS: High calcium, but not 1,25(OH)2 VD3 or RA, increases the expression of serine protease inhibitors in epidermal keratinocytes. Our findings contribute to the understanding of the mechanisms by which serine protease activities are regulated by serine proteases and related inhibitors in epidermal keratinocytes.

Pre-elafin is Involved in Ultraviolet-induced Keratinocyte Apoptosis via Pro-caspase-3 Activation Associated with Cystatin-A Down-regulation.

Pre-elafin controls keratinocyte integrity via cornified envelope formation and inhibition of desquamation, but its role in ultraviolet (UV)-induced keratinocyte apoptosis is unknown. This study examined the role of pre-elafin in volunteer skin samples and primary cultured normal human keratinocytes irradiated with phototoxic doses of UVA/narrow-band UVB, and in keratinocytes with pre-elafin overexpression/knockdown, under conditions of low and high calcium. Phototoxic doses of UV increased pre-elafin mRNA and protein expression in inverse proportion to keratinocyte survival. Pre-elafin overexpression under conditions of low calcium, which, in contrast to conditions of high calcium, was localized to the cytoplasm, increased keratinocyte apoptosis, whereas knockdown inhibited UV-induced apoptosis. Pre-elafin was co-localized with, but not bound to, cleaved caspase-3. Pre-elafin reduced cystatin-A expression, which was bound to pro-caspase-3. In conclusion, UV phototoxicity-induced pre-elafin inside keratinocytes prior to cornified envelope formation could be involved in UV-induced keratinocyte apoptosis via cystatin-A downregulation resulting in pro-caspase-3 activation.

Anti-inflammatory Elafin in human fetal membranes.

OBJECTIVE: Elafin is a low molecular weight protein with antileukoproteinase, anti-inflammatory, antibacterial and immunomodulating properties. The profile of Elafin in fetal membranes is not well characterized. This study determined the changes in Elafin expression and concentration in human fetal membrane from patients with preterm prelabor rupture of membranes (PPROM) and in vitro in response to intra-amniotic polymicrobial pathogens. METHOD: Elafin messenger RNA (mRNA) expressions were studied in fetal membranes from PPROM, normal term as well as in normal term not in labor membranes in an organ explant system treated (24 h) with lipopolysaccharide (LPS), using quantitative reverse transcription-polymerase chain reaction (RT-PCR). Enzyme-linked immunosorbent assay (ELISA) measured Elafin concentrations in culture supernatants from tissues treated with LPS and polybacterial combinations of heat-inactivated Mycoplasma hominis (MH), Ureaplasma urealyticum (UU) and Gardnerella vaginalis (GV). RESULTS: Elafin mRNA expression in fetal membranes from women with PPROM was significantly higher compared to women who delivered at term after normal pregnancy (5.09±3.50 vs. 11.71±2.21; P<0.05). In vitro, LPS-stimulated membranes showed a significantly increased Elafin m-RNA expression (P<0.05). However, the protein levels after LPS stimulation was not changed. Similarly, polymicrobial-treated fetal membranes also showed no changes in Elafin protein concentrations compared to untreated controls. CONCLUSION: Higher Elafin expression in PPROM fetal membranes suggests a host response to an inflammatory pathology. However, lack of Elafin response to LPS and polymicrobial treatment is indicative of the minimal anti-inflammatory impact of this molecule in fetal membranes.

Reduction of Mitochondria-Endoplasmic Reticulum Interactions by Acetylcholine Protects Human Umbilical Vein Endothelial Cells From Hypoxia/Reoxygenation Injury.

OBJECTIVE: We explored the role of endoplasmic reticulum (ER)-mitochondria Ca(2+) cross talk involving voltage-dependent anion channel-1 (VDAC1)/glucose-regulated protein 75/inositol 1,4,5-trisphosphate receptor 1 complex and mitofusin 2 in endothelial cells during hypoxia/reoxygenation (H/R), and investigated the protective effects of acetylcholine. APPROACH AND RESULTS: Acetylcholine treatment during reoxygenation prevented intracellular and mitochondrial Ca(2+) increases and alleviated ER Ca(2+) depletion during H/R in human umbilical vein endothelial cells. Consequently, acetylcholine enhanced mitochondrial membrane potential and inhibited proapoptotic cascades, thereby reducing cell death and preserving endothelial ultrastructure. This effect was likely mediated by the type-3 muscarinic acetylcholine receptor and the phosphatidylinositol 3-kinase/Akt pathway. In addition, interactions among members of the VDAC1/glucose-regulated protein 75/inositol 1,4,5-trisphosphate receptor 1 complex were increased after H/R and were associated with mitochondrial Ca(2+) overload and cell death. Inhibition of the partner of the Ca(2+) channeling complex (VDAC1 siRNA) or a reduction in ER-mitochondria tethering (mitofusin 2 siRNA) prevented the increased protein interaction within the complex and reduced mitochondrial Ca(2+) accumulation and subsequent endothelial cell death after H/R. Intriguingly, acetylcholine could modulate ER-mitochondria Ca(2+) cross talk by inhibiting the VDAC1/glucose-regulated protein 75/inositol 1,4,5-trisphosphate receptor 1 complex and mitofusin 2 expression. Phosphatidylinositol 3-kinase siRNA diminished acetylcholine-mediated inhibition of mitochondrial Ca(2+) overload and VDAC1/glucose-regulated protein 75/inositol 1,4,5-trisphosphate receptor 1 complex formation induced by H/R. CONCLUSIONS: Our data suggest that ER-mitochondria interplay plays an important role in reperfusion injury in the endothelium and may be a novel molecular target for endothelial protection. Acetylcholine attenuates both intracellular and mitochondrial Ca(2+) overload and protects endothelial cells from H/R injury, presumably by disrupting the ER-mitochondria interaction.

Deposition of elafin in the involved vascular wall of neutrophil-mediated cutaneous vasculitis.

BACKGROUND: Neutrophil elastase plays an important role in skin inflammation induced by neutrophil infiltration. Elafin is an inducible elastase inhibitor expressed by keratinocytes, and is known to be involved in pathogenesis of neutrophilic skin disorders such as psoriasis. METHODS: Immunohistochemical studies of elafin expression in the cases of vasculitis were performed. Induction of elafin expression in cultured vascular cells and its effect on neutrophil migration were studied in vitro. RESULTS: A positive immunoreactivity was detected in polyarteritis nodosa, giant cell arteritis and Schönlein-Henoch purpura, but no immunoreactivity was found in Churg-Strauss syndrome. Elafin expression in cultured venous endothelial cells and arterial smooth muscle cells was undetectable, but induced by interleukin-1ß (IL-1ß) and IL-8. Elafin inhibited the elastin peptide-induced neutrophil chemotaxis at the concentration of 10(-8) -10(-5) mol/L. CONCLUSION: Elafin deposition induced by cytokines (IL-1ß or IL-8) will be an important regulator for the progress of leucocytoclastic vasculitis by functioning as an inhibitor for neutrophil chemotaxis as well as for vascular elastin degradation.

Protective effects of elafin against adult asthma.

BACKGROUND: Elafin inhibits serine proteases, such as human neutrophil elastase and proteinase 3, to prevent excessive damage during inflammation. However, the relationship between elafin and asthma is still unclear. Microarray technology was used to evaluate smoking- and asthma-related biomarkers in a discovery-driven manner. We identified candidate genes, e.g., proteinase inhibitor 3 (PI3), related to asthma and smoking from gene expression microarray data sets and evaluated their potential as biomarkers for asthma. METHODS: We used human genome microarray data sets from smoking- and asthma-related gene expression data sets and performed real-time quantitative polymerase chain reaction to measure and validate differences in gene expression. We also recruited adult patients with asthma and age- and sex-matched control patients who were administered a structured questionnaire and evaluated for lung function and plasma elafin levels, which are encoded by the PI3 gene. RESULTS: Six significantly altered candidate genes, PI3, protein kinase C iota, phosphoserine phosphatase, IQ motif-containing GTPase activating protein 1, interleukin 13 receptor α 1, and signal transducing adaptor molecule SH3 domain and ITAM motif 2, were identified from comparisons across the four asthma- and four smoking-related data sets included in this study. An in vitro study of human airway epithelial cells (A549) and a human monocytic cell line (THP-1) demonstrated that PI3 messenger RNA levels were significantly altered by nicotine exposure. Elafin concentration was significantly higher in control patients than in patients with asthma (p < 0.001). The plasma elafin concentration in the highest quartile (≥12.69 ng/mL) was inversely associated with asthma (adjusted odds ratio 0.122 [95% confidence interval, 0.053-0.278]) compared with the lowest quartile (<5.82 ng/mL) after adjusting for age, sex, smoking status, waist-to-hip ratio, percentage predicted forced expiratory volume in 1 second, cockroaches in the home, incense burning, and family history. CONCLUSION: Our study revealed that high elafin levels identified in smoking- and asthma-related microarray data sets and an epidemiologic study significantly reduced the risk of asthma. Further studies of elafin as a potential therapy for asthma are warranted.

Analysis of caveolin-1 and phosphoinositol-3 kinase expression in primary uveal melanomas.

BACKGROUND: To evaluate the regulation of blood supply in primary uveal melanomas through caveolin-1 (Cav-1)/phosphoinositol-3 kinase (PI3K). METHODS: The expression of Cav-1 and PI3K was analysed in 51 paraffin sections of metastatic (n = 30) and non-metastastic uveal melanomas (n = 21). Two trained observers quantified Cav-1 and PI3K immunofluorescensce expression by determining intensity of staining and percentage of positive cells. The expression was correlated with known prognostic factors. Besides angiogenesis by means of endoglin expression, the normal vasculature (von Willebrand Factor expression) was evaluated semi-quantitatively. Vasculogenic mimicry (VM) was analysed by CD31/PAS staining. RESULTS: All examined specimens expressed Cav-1 with a mean of 90.34% Cav-1 positive cells (range, 3.23-100%). Metastatic disease was associated with a higher Cav-1 expression. The correlation of Cav-1 with well-established prognostic factors showed a significant association between Cav-1 expression and largest tumour diameter (P = 0.022), tumour node metastasis classification (P = 0.008) and invasion of optic nerve head (P = 0.048). PI3K was expressed by all uveal melanomas with a mean of 87.28% cells showing PI3K expression. A higher level of PI3K was significantly associated with larger height (P = 0.042) and progressed tumour node metastasis stage (P = 0.016). The percentage of PI3K and Cav-1 positive cells were significantly associated (P = 0.034). For PI3K and Cav-1 expression a non-significant association with VM was shown (P = 0.064 and P = 0.072, respectively). No correlation of PI3K or Cav-1 with angiogenesis or mature vasculature was seen (P > 0.05). CONCLUSIONS: Cav-1 expression may be especially up-regulated in larger uveal melanomas. As it was correlated with PI3K expression and VM in this series of uveal melanoma, Cav-1 might induce the formation of VM via the PI3K-signalling cascade.

[Expression of elafin in peripheral blood in inflammatory bowel disease patients and its clinical significance].

OBJECTIVE: To quantify the expression of elafin mRNA in peripheral blood in patients with inflammatory bowel disease (IBD) and to explore its value in assessment of the activity and severity of IBD. METHODS: From July 1 2015 to August 15 2015, 23 patients with IBD admitted to Peking University First Hospital were selected, including 15 cases with ulcerative colitis (UC) and 8 cases with Crohn's disease (CD). Among those, 5 cases were in remission (UC 3, CD 2), 6 cases were mild active (UC 3, CD 3), 3 cases were moderate active (UC 1, CD 2), and 9 cases were severe active (UC 8, CD 1). A total of 21 healthy individuals were selected as the control group. Peripheral blood samples of IBD patients and healthy controls were collected. The expression of elafin mRNA in peripheral blood leukocytes was detected by fluorescence quantitative real-time PCR. Mann-Whitney test was performed for comparison between the two groups. The correlation between the expression of elafin mRNA in peripheral blood and IBD activity score was analyzed by Pearson correlation analysis after transformation of variables. RESULTS: The median expression of elafin mRNA in peripheral blood leukocytes in IBD group and control group was 0.005 8 (0.000 2, 0.043 5) and 0.015 3 (0.002 1, 0.175 8), respectively, with no significant difference (P>0.05). However, in the active IBD patients it was lower than that in the controls (0.004 6 (0.000 2, 0.034 8) vs 0.015 3 (0.002 1, 0.175 8), P<0.05) and also lower than that in the remission patients(0.004 6 (0.000 2, 0.034 8) vs 0.023 1 (0.012 6, 0.043 5), P<0.05); in the active UC patients it was lower than that in the controls(0.003 7 (0.000 2, 0.027 0) vs 0.015 3 (0.002 1, 0.175 8), P<0.05). The expression of elafin mRNA in peripheral blood was negatively correlated with modified Mayo score in UC patients (r=-0.513, P<0.05) and with the Crohn's Disease Activity Index (CDAI) of Best score in CD patients (r=-0.889, P<0.05). CONCLUSION: The expression of elafin mRNA in peripheral blood in active IBD patients is decreased, which may be correlated with the activity of IBD, and negatively correlated with corresponding disease activity score, suggesting that it may play a protective role in IBD and may be helpful in predicting disease activity.

Ionizing radiation-inducible miR-494 promotes glioma cell invasion through EGFR stabilization by targeting p190B rhoGAP.

MicroRNAs (miRNAs) play an important role in various stages of tumor progression. miR-494, which we had previously identified as a miRNA induced by ionizing radiation (IR) in the glioma cell line U-251, was observed to enhance invasion of U-251 cells by activating MMP-2. The miR-494-induced invasive potential was accompanied by, and dependent on, epidermal growth factor receptor (EGFR) upregulation and the activation of its downstream signaling constituents, Akt and ERK. The upregulation of EGFR by miR-494 involved the suppression of lysosomal protein turnover. Among the putative target proteins tested, p190B RhoGAP (p190B) was downregulated by miR-494, and its reduced expression was responsible for the increase in EGFR expression. A reporter assay using a luciferase construct containing p190B 3'-untranslated region (3'UTR) confirmed that p190B is a direct target of miR-494. Downregulation of p190B by small interfering RNA (siRNA) transfection closely mimicked the outcomes of miR-494 transfection, and showed increased EGFR expression, MMP-2 secretion, and invasion. Ectopic expression of p190B suppressed the miR-494-induced EGFR upregulation and invasion promotion, thereby suggesting that p190B depletion is critical for the invasion-promoting action of miR-494. Collectively, our results suggest a novel function for miR-494 and its potential application as a target to control invasiveness in cancer therapy.

Serine protease inhibitors protect better than IL-10 and TGF-ß anti-inflammatory cytokines against mouse colitis when delivered by recombinant lactococci.

BACKGROUND: Different studies have described the successful use of recombinant lactic acid bacteria (recLAB) to deliver anti-inflammatory molecules at the mucosal level to treat Inflammatory Bowel Disease (IBD). METHODS: In order to identify the best strategy to treat IBD using recLAB, we compared the efficacy of different recombinant strains of Lactococcus lactis (the model LAB) secreting two types of anti-inflammatory molecules: cytokines (IL-10 and TGF-ß1) and serine protease inhibitors (Elafin and Secretory Leukocyte Protease Inhibitor: SLPI), using a dextran sulfate sodium (DSS)-induced mouse model of colitis. RESULTS: Our results show that oral administration of recombinant L. lactis strains expressing either IL-10 or TGF-ß1 display moderate anti-inflammatory effects in inflamed mice and only for some clinical parameters. In contrast, delivery of either serine protease inhibitors Elafin or SLPI by recLAB led to a significant reduction of intestinal inflammation for all clinical parameters tested. Since the best results were obtained with Elafin-producing L. lactis strain, we then tried to enhance Elafin expression and hence its delivery rate by producing it in a L. lactis mutant strain inactivated in its major housekeeping protease, HtrA. Strikingly, a higher reduction of intestinal inflammation in DSS-treated mice was observed with the Elafin-overproducing htrA strain suggesting a dose-dependent Elafin effect. CONCLUSIONS: Altogether, these results strongly suggest that serine protease inhibitors are the most efficient anti-inflammatory molecules to be delivered by recLAB at the mucosal level for IBD treatment.

Perfusion Intensity Correlates with Expression Levels of Psoriasis-Related Genes and Proteins.

BACKGROUND: Previous research revealed heterogeneity in the perfusion intensity within clinically homogenous-appearing plaques, without differences in erythema. In addition, an increased perfusion was found within the perilesional skin. This raises the question whether the heterogeneity in perfusion found both inside and outside a lesion influences the expression levels of genes and proteins involved in the pathogenesis of psoriasis. OBJECTIVES: To correlate the perfusion intensity to mRNA and protein expression of genes associated with the pathogenesis of psoriasis and to visualize the dynamics of the perfusion intensity over time using laser Doppler perfusion imaging. METHODS: Fourteen patients with plaque psoriasis were included. The superficial microcirculation and clinical local scores (single usability metric, SUM, scores) were analysed in one representative lesion every 2 weeks. After 8 weeks 4 biopsies were taken, one from a highly perfused area (hotspot) and one from a low perfusion area (coldspot) of the lesional skin, one biopsy from the highly perfused perilesional skin and one from the distant uninvolved skin. RESULTS: Statistically significant differences in mRNA and protein expression, including IL-17 and TBX21/T-Bet, were found between hotspots and coldspots, and between the highly perfused perilesional and the uninvolved skin. Hotspots tend to remain on the same location during 8 weeks of follow-up. CONCLUSIONS: Within homogenous-appearing psoriatic plaques, there are remarkable differences in mRNA and protein levels, which are correlated with the perfusion intensity and can be detected by using laser Doppler perfusion imaging. In addition, differences in mRNA and protein expression between the highly perfused perilesional skin and the uninvolved skin were found, indicating that several biological changes occur well before clinical changes become manifest.

Functional characterization of polymorphisms in the peptidase inhibitor 3 (elafin) gene and validation of their contribution to risk of acute respiratory distress syndrome.

Elafin (peptidase inhibitor 3 [PI3]) and its biologically active precursor, pre-elafin, are neutrophil serine proteinase inhibitors with an important role in preventing excessive tissue injury during inflammatory events. Recently, we reported an association between single-nucleotide polymorphism (SNP) rs2664581 in the PI3 gene, increased risk of acute respiratory distress syndrome (ARDS) and pre-elafin circulating levels. This study aims to validate the legitimacy of this association by using a cohort of patients who met the criteria for systemic inflammatory response syndrome and were at risk of developing ARDS (n = 840). A comprehensive functional study of SNPs in PI3 gene was also performed. Luciferase assays and electrophoretic mobility shift assays were conducted to determine the functional relevance of promoter region variants. The effect of the coding SNP rs2664581 on the neutrophil elastase inhibitory activity and transglutaminase binding properties of pre-elafin was also investigated. The variant allele of rs2664581 (C) was significantly associated with increased ARDS risk, mainly among subjects with sepsis (odds ratio = 1.44; 95% confidence interval = 1.04-1.99; P = 0.0276, adjusted by age, sex, and Acute Physiology and Chronic Health Evaluation III). Pre-elafin recombinant protein carrying the amino acid change associated with rs2664581 (Thr34Pro, mutant protein [MT]) had greater capacity to undergo transglutaminase-mediated cross-linking to immobilized fibronectin than wild-type protein in vitro (P < 0.003). No differences were observed in the neutrophil elastase inhibitory activities of wild-type versus MT proteins. In addition, the risk allele-promoter construct had significantly lower cytokine-induced transcriptional activity. Electrophoretic mobility shift assay results indicated a differential binding of nuclear proteins to the G and A alleles of SNP -338G > A. Our results confirm the association between SNP rs2664581 and enhanced risk of ARDS, further supporting the role of PI3 in ARDS development. SNPs in the PI3 locus may act synergistically by regulating PI3 gene expression and pre-elafin biological functions.

Mutations in the polybasic juxtamembrane sequence of both plasma membrane- and endoplasmic reticulum-localized epidermal growth factor receptors confer ligand-independent cell transformation.

Deregulation of ErbB receptor-tyrosine kinases is a hallmark of many human cancers. Conserved in the ErbB family is a cluster of basic amino acid residues in the cytoplasmic juxtamembrane region. We found that charge-silencing mutagenesis within this juxtamembrane region of the epidermal growth factor receptor (EGFR) results in the generation of a mutant receptor (EGFR Mut R1-6) that spontaneously transforms NIH 3T3 cells in a ligand-independent manner. A similar mutant with one additional basic residue, EGFR Mut R1-5, fails to exhibit ligand-independent transformation. The capacity of EGFR Mut R1-6 to mediate this transformation is maintained when this mutant is retained in the endoplasmic reticulum via a single point mutation, L393H, which we describe. We show that EGFR Mut R1-6 with or without L393H exhibits enhanced basal tyrosine phosphorylation when ectopically expressed, and the ligand-independent transforming activity of EGFR Mut R1-6 is sensitive to inhibition of EGFR kinase activity and is particularly dependent on PI3K and mTOR activity. Similar to EGFR Mut R1-6/L393H in NIH 3T3 cells, EGFR variant type III, a highly oncogenic mutant form of EGFR linked to human brain cancers, confers transforming activity while it is wholly endoplasmic reticulum-retained in U87 cells. Our findings highlight the importance of the polybasic juxtamembrane sequence in regulating the oncogenic potential of EGFR signaling.

Elafin is downregulated during breast and ovarian tumorigenesis but its residual expression predicts recurrence.

INTRODUCTION: Elafin is an endogenous serine protease inhibitor. The majority of breast cancer cell lines lack elafin expression compared to human mammary epithelial cells. In this study, we hypothesized that elafin is downregulated during breast and ovarian tumorigenesis. METHODS: We examined elafin expression by immunohistochemistry (IHC) in specimens of normal breast tissue (n = 24), ductal carcinoma in situ (DCIS) (n = 54), and invasive breast cancer (n = 793). IHC analysis of elafin expression was also performed in normal fallopian tube tissue (n = 20), ovarian cystadenomas (n = 9), borderline ovarian tumors (n = 21), and invasive ovarian carcinomas (n = 216). To understand the significance of elafin in luminal breast cancer cell lines, wild-type or M25G elafin (lacking the protease inhibitory function) were exogenously expressed in MCF-7 and T47D cells. RESULTS: Elafin expression was downregulated in 24% of DCIS and 83% of invasive breast tumors when compared to elafin expression in the normal mammary epithelium. However, the presence of elafin-positive cells in invasive breast tumors, even at low frequency, correlated with poor recurrence-free survival (RFS), reduced overall survival (OS), and clinicopathological markers of aggressive tumor behavior. Elafin-positive cells were an especially strong and independent prognostic marker of reduced RFS in IHC-defined luminal A-like tumors. Elafin was also downregulated in 33% of ovarian cystadenomas, 43% of borderline ovarian tumors, and 86% of invasive ovarian carcinomas when compared to elafin expression in the normal fallopian tube. In ovarian tumors, elafin-positive cells were correlated with reduced RFS, OS and disease-specific survival (DSS) only in stage I/II patients and not in stage III/IV patients. Notably, exogenous expression of elafin or elafin M25G in the luminal breast cancer cell lines MCF-7 and T47D significantly decreased cell proliferation in a protease inhibitory domain-independent manner. CONCLUSIONS: Elafin predicts poor outcome in breast and ovarian cancer patients and delineates a subset of endocrine receptor-positive breast cancer patients susceptible to recurrence who could benefit from more aggressive intervention. Our in vitro results suggest that elafin arrests luminal breast cancer cells, perhaps suggesting a role in tumor dormancy.

Prostate cancer ETS rearrangements switch a cell migration gene expression program from RAS/ERK to PI3K/AKT regulation.

BACKGROUND: The RAS/ERK and PI3K/AKT pathways induce oncogenic gene expression programs and are commonly activated together in cancer cells. Often, RAS/ERK signaling is activated by mutation of the RAS or RAF oncogenes, and PI3K/AKT is activated by loss of the tumor suppressor PTEN. In prostate cancer, PTEN deletions are common, but, unlike other carcinomas, RAS and RAF mutations are rare. We have previously shown that over-expression of "oncogenic" ETS transcription factors, which occurs in about one-half of prostate tumors due to chromosome rearrangement, can bypass the need for RAS/ERK signaling in the activation of a cell migration gene expression program. In this study we test the role of RAS/ERK and PI3K/AKT signaling in the function of oncogenic ETS proteins. RESULTS: We find that oncogenic ETS expression negatively correlates with RAS and RAF mutations in prostate tumors. Furthermore, the oncogenic ETS transcription factors only increased cell migration in the absence of RAS/ERK activation. In contrast to RAS/ERK, it has been reported that oncogenic ETS expression positively correlates with PI3K/AKT activation. We identified a mechanistic explanation for this finding by showing that oncogenic ETS proteins required AKT signaling to activate a cell migration gene expression program through ETS/AP-1 binding sequences. Levels of pAKT correlated with the ability of oncogenic ETS proteins to increase cell migration, but this process did not require mTORC1. CONCLUSIONS: Our findings indicate that oncogenic ETS rearrangements cause a cell migration gene expression program to switch from RAS/ERK control to PI3K/AKT control and provide a possible explanation for the high frequency of PTEN, but not RAS/RAF mutations in prostate cancer.