Intestinal Permeability and Dysbiosis in Female Patients with Recurrent Cystitis: A Pilot Study.

Recurrent cystitis (RC) is a common disease, especially in females. Anatomical, behavioral and genetic predisposing factors are associated with the ascending retrograde route, which often causes bladder infections. RC seems to be mainly caused by agents derived from the intestinal microbiota, and most frequently by Escherichia coli. Intestinal contiguity contributes to the etiopathogenesis of RC and an alteration in intestinal permeability could have a major role in RC. The aim of this pilot study is to assess gut microbiome dysbiosis and intestinal permeability in female patients with RC. Patients with RC (n = 16) were enrolled and compared with healthy female subjects (n = 15) and patients with chronic gastrointestinal (GI) disorders (n = 238). We calculated the Acute Cystitis Symptom Score/Urinary Tract Infection Symptom Assessment (ACSS/UTISA) and Gastrointestinal Symptom Rating Scale (GSRS) scores and evaluated intestinal permeability and the fecal microbiome in the first two cohorts. Patients with RC showed an increased prevalence of gastrointestinal symptoms compared with healthy controls. Of the patients with RC, 88% showed an increased intestinal permeability with reduced biodiversity of gut microbiota compared to healthy controls, and 68% of the RC patients had a final diagnosis of gastrointestinal disease. Similarly, GI patients reported a higher incidence of urinary symptoms with a diagnosis of RC in 20%. Gut barrier impairment seems to play a major role in the pathogenesis of RC. Further studies are necessary to elucidate the role of microbiota and intestinal permeability in urinary tract infections.

A Shaving Proteomic Approach to Unveil Surface Proteins Modulation of Multi-Drug Resistant Pseudomonas aeruginosa Strains Isolated From Cystic Fibrosis Patients.

Cystic fibrosis (CF) is the most common rare disease caused by a mutation of the CF transmembrane conductance regulator gene encoding a channel protein of the apical membrane of epithelial cells leading to alteration of Na+ and K+ transport, hence inducing accumulation of dense and sticky mucus and promoting recurrent airway infections. The most detected bacterium in CF patients is Pseudomonas aeruginosa (PA) which causes chronic colonization, requiring stringent antibiotic therapies that, in turn induces multi-drug resistance. Despite eradication attempts at the first infection, the bacterium is able to utilize several adaptation mechanisms to survive in hostile environments such as the CF lung. Its adaptive machinery includes modulation of surface molecules such as efflux pumps, flagellum, pili and other virulence factors. In the present study we compared surface protein expression of PA multi- and pan-drug resistant strains to wild-type antibiotic-sensitive strains, isolated from the airways of CF patients with chronic colonization and recent infection, respectively. After shaving with trypsin, microbial peptides were analyzed by tandem-mass spectrometry on a high-resolution platform that allowed the identification of 174 differentially modulated proteins localized in the region from extracellular space to cytoplasmic membrane. Biofilm assay was performed to characterize all 26 PA strains in term of biofilm production. Among the differentially expressed proteins, 17 were associated to the virulome (e.g., Tse2, Tse5, Tsi1, PilF, FliY, B-type flagellin, FliM, PyoS5), six to the resistome (e.g., OprJ, LptD) and five to the biofilm reservoir (e.g., AlgF, PlsD). The biofilm assay characterized chronic antibiotic-resistant isolates as weaker biofilm producers than wild-type strains. Our results suggest the loss of PA early virulence factors (e.g., pili and flagella) and later expression of virulence traits (e.g., secretion systems proteins) as an indicator of PA adaptation and persistence in the CF lung environment. To our knowledge, this is the first study that, applying a shaving proteomic approach, describes adaptation processes of a large collection of PA clinical strains isolated from CF patients in early and chronic infection phases.

Focal adhesion kinase inhibitor TAE226 combined with Sorafenib slows down hepatocellular carcinoma by multiple epigenetic effects.

BACKGROUND: Hepatocellular carcinoma (HCC) is one of the most common and lethal malignant tumours worldwide. Sorafenib (SOR) is one of the most effective single-drug systemic therapy against advanced HCC, but the identification of novel combination regimens for a continued improvement in overall survival is a big challenge. Recent studies highlighted the crucial role of focal adhesion kinase (FAK) in HCC growth. The aim of this study was to investigate the antitumor effects of three different FAK inhibitors (FAKi), alone or in combination with SOR, using in vitro and in vivo models of HCC. METHODS: The effect of PND1186, PF431396, TAE226 on cell viability was compared to SOR. Among them TAE226, emerging as the most effective FAKi, was tested alone or in combination with SOR using 2D/3D human HCC cell line cultures and HCC xenograft murine models. The mechanisms of action were assessed by gene/protein expression and imaging approaches, combined with high-throughput methods. RESULTS: TAE226 was the more effective FAKi to be combined with SOR against HCC. Combined TAE226 and SOR treatment reduced HCC growth both in vitro and in vivo by affecting tumour-promoting gene expression and inducing epigenetic changes via dysregulation of FAK nuclear interactome. We characterized a novel nuclear functional interaction between FAK and the NuRD complex. TAE226-mediated FAK depletion and SOR-promoted MAPK down-modulation caused a decrease in the nuclear amount of HDAC1/2 and a consequent increase of the histone H3 lysine 27 acetylation, thus counteracting histone H3 lysine 27 trimethylation. CONCLUSIONS: Altogether, our findings provide the first evidence that TAE226 combined with SOR efficiently reduces HCC growth in vitro and in vivo. Also, our data highlight that deep analysis of FAK nuclear interactome may lead to the identification of new promising targets for HCC therapy.

Different responses of PC12 cells to different pro-nerve growth factor protein variants.

The present work aimed to explore the innovative hypothesis that different transcript/protein variants of a pro-neurotrophin may generate different biological outcomes in a cellular system. Nerve growth factor (NGF) is important in the development and progression of neurodegenerative and cancer conditions. Mature NGF (mNGF) originates from a precursor, proNGF, produced in mouse in two major variants, proNGF-A and proNGF-B. Different receptors bind mNGF and proNGF, generating neurotrophic or neurotoxic outcomes. It is known that dysregulation in the proNGF/mNGF ratio and in NGF-receptors expression affects brain homeostasis. To date, however, the specific roles of the two major proNGF variants remain unexplored. Here we attempted a first characterization of the possible differential effects of proNGF-A and proNGF-B on viability, differentiation and endogenous ngf gene expression in the PC12 cell line. We also investigated the differential involvement of NGF receptors in the actions of proNGF. We found that native mouse mNGF, proNGF-A and proNGF-B elicited different effects on PC12 cell survival and differentiation. Only mNGF and proNGF-A promoted neurotrophic responses when all NGF receptors are exposed at the cell surface. Tropomyosine receptor kinase A (TrkA) blockade inhibited cell differentiation, regardless of which NGF was added to culture media. Only proNGF-A exerted a pro-survival effect when TrkA was inhibited. Conversely, proNGF-B exerted differentiative effects when the p75 neurotrophin receptor (p75NTR) was antagonized. Stimulation with NGF variants differentially regulated the autocrine production of distinct proNgf mRNA. Overall, our findings suggest that mNGF and proNGF-A may elicit similar neurotrophic effects, not necessarily linked to activation of the same NGF-receptor, while the action of proNGF-B may be determined by the NGF-receptors balance. Thus, the proposed involvement of proNGF/NGF on the development and progression of neurodegenerative and tumor conditions may depend on the NGF-receptors balance, on specific NGF trancript expression and on the proNGF protein variant ratio.

Mass spectrometry characterization of DOTA-Nimotuzumab conjugate as precursor of an innovative ß- tracer suitable in radio-guided surgery.

The aim of the present work has been the mass spectrometry characterization of the Nimotuzumab (NIM) antibody chemically modified with the bifunctional chelating agent para-S-2-(4-isothiocyanatobenzyl)-1,4,7,10-tetraaza cyclododecanetetraacetic acid (p-SCN-Bn-DOTA). The conjugate, upon labeling with the pure ß--emitter 90Y3+, could represent a promising candidate as radiotracer for an innovative radio-guided surgery (RGS) technique, developed and patented by researchers of our group, which uses a probe system for intraoperative detection of tumor residues exploiting the selective uptake of ß--emitting tracers. The results reported in this study show that multiple DOTA molecules bind to lysine residues of both light and heavy chains of the antibody and, probably, some of them are linked to the variable region of antibody. Moreover, the new mass spectrometric analysis highlights the presence of unreacted NIM in the final product. The information obtained by this work is of fundamental importance in the perspective to utilize this conjugate as a radiocompound after its labeling with 90Y3+ radioisotope. Indeed, the conjugation efficiency and the presence of unreacted NIM affect the specific activity of the final radiotracer which binds specific receptor.

Structural studies and SH3 domain binding properties of a human antiviral salivary proline-rich peptide.

Human saliva contains hundreds of small proline-rich peptides originated by the proteolytic cleavage of the salivary basic Proline-Rich Proteins. Nevertheless only for few of them a specific biological activity has been assigned to date. Among them, the 1932 Da peptide (p1932) has been patented as an anti-HIV agent. In order to shed light on the possible mechanism of action of this peptide, we assessed in this study, by means of molecular dynamics calculations, circular dichroism and FTIR spectroscopic techniques, that p1932 has an intrinsic propensity to adopt a polyproline-II helix arrangement. This structural feature combined with the presence of PxxP motifs in its primary structure, represents an essential property for the exploitation of several biological activities. Next to these findings, we recently demonstrated the ability of this peptide to be internalized within cells of the oral mucosa, thus we focused onto a possible intracellular target, represented by the SH3 domains family. Its ability to interact with selected SH3 domains was finally assayed by Surface Plasmon Resonance spectroscopy. As a result, only Fyn, Hck, and c-Src SH3 domains gave positive results in terms of interaction, showing dissociation constants ranging from nanomolar to micromolar values having the best performer a KD of 148 nM. It is noteworthy that all the interacting domains belong to the Src kinases family, suggesting a role for p1932 as a modulator of the signal transduction pathways mediated by these kinases. © 2016 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 106: 714-725, 2016.

Characterization of the Protein Components of Matrix Stones Sheds Light on S100-A8 and S100-A9 Relevance in the Inflammatory Pathogenesis of These Rare Renal Calculi.

PURPOSE: Among the different types of kidney stones, matrix stones are uncommon urinary calculi composed of a soft, pliable, amorphous substance with little crystalline content. To gain insight into the pathogenesis we investigated the protein component by analyzing the proteomic profiles of surgically removed matrix stones. MATERIALS AND METHODS: A total of 5 stones were harvested from 4 patients who underwent surgery for medical reasons at 3 clinical centers during a 7-year period. Matrix stone proteome characterization was performed by mass spectrometry based techniques using an integrated top-down/bottom-up proteomic platform. RESULTS: We identified 142 nonredundant proteins and peptides across all samples. Neutrophil defensin 1, and proteins S100-A8 and S100-A9 were the main components of these renal calculi. CONCLUSIONS: The abundance of identified inflammatory molecules points to an inflammatory process as the event that initializes soft calculi formation rather than as a consequence of such formation. The post-translational oxidative changes in S100-A8 and A9, and the presence of thymosin ß-4, granulins and ubiquitin also suggest the intervention of host defenses through a superimposed, vigorous counter inflammatory process. The post-translational changes seen in the proteins and peptides, and the known self-assembling capability of S100-A8 and S100-A9 probably explain the gelatinous consistency of these stones.

Antagonistic Effect of a Salivary Proline-Rich Peptide on the Cytosolic Ca2+ Mobilization Induced by Progesterone in Oral Squamous Cancer Cells.

A salivary proline-rich peptide of 1932 Da showed a dose-dependent antagonistic effect on the cytosolic Ca2+ mobilization induced by progesterone in a tongue squamous carcinoma cell line. Structure-activity studies showed that the activity of the peptide resides in the C-terminal region characterized by a proline stretch flanked by basic residues. Furthermore, lack of activity of the retro-inverso peptide analogue suggested the involvement of stereospecific recognition. Mass spectrometry-based shotgun analysis, combined with Western blotting tests and biochemical data obtained with the Progesterone Receptor Membrane Component 1 (PGRMC1) inhibitor AG205, showed strong evidence that p1932 performs its modulatory action through an interaction with the progesterone receptor PGRMC1, which is predominantly expressed in this cell line and, clearly, plays a role in progesterone induced Ca2+ response. Thus, our results point to p1932 as a modulator of the transduction signal pathway mediated by this protein and, given a well-established involvement of PGRMC1 in tumorigenesis, highlight a possible therapeutic potential of p1932 for the treatment of oral cancer.

Proteomic profiling of ATM kinase proficient and deficient cell lines upon blockage of proteasome activity.

Ataxia Telangiectasia Mutated (ATM) protein kinase is a key effector in the modulation of the functionality of some important stress responses, including DNA damage and oxidative stress response, and its deficiency is the hallmark of Ataxia Telangiectasia (A-T), a rare genetic disorder. ATM modulates the activity of hundreds of target proteins, essential for the correct balance between proliferation and cell death. The aim of this study is to evaluate the phenotypic adaptation at the protein level both in basal condition and in presence of proteasome blockage in order to identify the molecules whose level and stability are modulated through ATM expression. We pursued a comparative analysis of ATM deficient and proficient lymphoblastoid cells by label-free shotgun proteomic experiments comparing the panel of proteins differentially expressed. Through a non-supervised comparative bioinformatic analysis these data provided an insight on the functional role of ATM deficiency in cellular carbohydrate metabolism's regulation. This hypothesis has been demonstrated by targeted metabolic fingerprint analysis SRM (Selected Reaction Monitoring) on specific thermodynamic checkpoints of glycolysis. This article is part of a Special Issue entitled: Translational Proteomics.

TIMP3 overexpression in macrophages protects from insulin resistance, adipose inflammation, and nonalcoholic fatty liver disease in mice.

The tissue inhibitor of metalloproteinase (TIMP)3, a stromal protein that restrains the activity of proteases and receptors, is reduced in inflammatory metabolic disorders such as type 2 diabetes mellitus (T2DM) and atherosclerosis. We overexpressed Timp3 in mouse macrophages (MacT3) to analyze its potential antidiabetic and antiatherosclerotic effects. Transgenic mice with myeloid cells targeting overexpression of TIMP3 were generated and fed a high-fat diet for 20 weeks. Physical and metabolic phenotypes were determined. Inflammatory markers, lipid accumulation, and insulin sensitivity were measured in white adipose tissue (WAT), liver, and skeletal muscle. In a model of insulin resistance, MacT3 mice were more glucose tolerant and insulin sensitive than wild-type mice in both in vitro and in vivo tests. Molecular and biochemical analyses revealed that increased expression of TIMP3 restrained metabolic inflammation and stress-related pathways, including Jun NH2-terminal kinase and p38 kinase activation, in WAT and liver. TIMP3 overexpression in macrophages resulted in reduced activation of oxidative stress signals related to lipid peroxidation, protein carbonylation, and nitration in WAT and liver. Our data show that macrophage-specific overexpression of TIMP3 protects from metabolic inflammation and related metabolic disorders such as insulin resistance, glucose intolerance, and nonalcoholic steatohepatitis.

Proteomics investigation of human platelets in healthy donors and cystic fibrosis patients by shotgun nUPLC-MSE and 2DE: a comparative study.

Platelets are of pathophysiological relevance in haemostasis, wound repair, inflammation and cardiovascular disease. We have shown that human platelets express a biologically active Cystic Fibrosis Transmembrane Conductance Regulator, which is dysfunctional in Cystic Fibrosis (CF) patients, and regulate platelet responses related to inflammation and its resolution. In order to further elucidate platelet involvement in CF inflammation, we pursued a comparative proteomic analysis of cells from healthy donors and CF patients, in association with a non-supervised comparative analysis of the Gene Ontology. Our results, showing changes in the integrin signalling in CF, support a pro-inflammatory profile of CF platelets.

New insights into neuroblastoma cisplatin resistance: a comparative proteomic and meta-mining investigation.

Neuroblastoma is one of the most aggressive solid tumors in the childhood. Therapy resistance to anticancer drugs represents the major limitation to the effectiveness of clinical treatment. To better understand the mechanisms underlying cisplatin resistance, we performed a comparative proteomic study of the human neuroblastoma cell line SH-SY5Y and its cisplatin resistant counterpart by both the classical 2-DE electrophoresis coupled to mass spectrometry and the more innovative label-free nLC-MS(E). The differentially expressed proteins were classified by bioinformatic tools according to their biological functions and their involvement in several cellular processes. Moreover, a meta-mining investigation of protein ontologies was also performed on available data from previously published proteomics studies to highlight the modulation of significant cellular pathways, which may regulate the sensitivity of neuroblastoma to cisplatin. In particular, we hypothesized a major role of the transcription factor nuclear factor-erythroid 2-related factor 2 (Nrf2) pathway. Confocal microscopy experiments, enzyme assay, and Western blotting of proteins regulated by Nrf2 provided evidences that this pathway, playing a protective role in normal cells, may represent a potential novel target to control cisplatin resistance in neuroblastoma.

Markers of anti-oxidant response in tobacco smoke exposed subjects: a data-mining review.

Tobacco smoke exposure is the cause of exaggerated inflammatory responses and tissue destruction leading to chronic bronchitis and emphysema. A number of studies have used biochemical and immunological technologies to identify biomarkers of severity, risk and pharmacological target of disease. Recently, genomic and proteomic studies have been carried out to explore tobacco smoke-induced lung damage mechanisms. Eight of these studies, including 81 healthy non-smokers, 138 healthy smokers and 24 smokers with COPD, had open platform generated data available online and were reviewed in order to identify markers of smoke-induced damage by analyzing differential gene and protein expression in healthy individuals exposed to tobacco smoke in comparison with chronic obstructive pulmonary disease (COPD) smokers and healthy non-smokers. To this end the Ingenuity Pathways Analysis, a web-based application enables identifying the main biological functions and pathways, was used. The pathway most significantly associated with healthy smokers was the Nrf2-mediated Oxidative Stress Response (p-value < 0.01): out of the 22 genes/proteins identified in healthy smokers, 19 were up-regulated and three down-regulated, compared to non-smokers. Interestingly, four genes/proteins of the same pathway were differentially regulated in COPD, one up-regulated and three down-regulated, compared to healthy smokers. Moreover, in the comparison between COPD and healthy smokers, our analysis showed that the most relevant pathway was the Mitochondrial Dysfunction (p-value < 0.01) with 12 differentially regulated genes/proteins. This data-mining review supports the notion that Nrf2-regulated anti-oxidant genes play a central role in protection against tobacco smoke toxic effects and may be amenable to use as COPD risk biomarkers. Furthermore, this review suggests that mitochondrial dysfunction may be involved in the development of COPD.

Increased tumor necrosis factor alpha-converting enzyme activity induces insulin resistance and hepatosteatosis in mice.

UNLABELLED: Tumor necrosis factor alpha-converting enzyme (TACE, also known as ADAM17) was recently involved in the pathogenesis of insulin resistance. We observed that TACE activity was significantly higher in livers of mice fed a high-fat diet (HFD) for 1 month, and this activity was increased in liver > white adipose tissue > muscle after 5 months compared with chow control. In mouse hepatocytes, C(2)C(12) myocytes, and 3T3F442A adipocytes, TACE activity was triggered by palmitic acid, lipolysaccharide, high glucose, and high insulin. TACE overexpression significantly impaired insulin-dependent phosphorylation of AKT, GSK3, and FoxO1 in mouse hepatocytes. To test the role of TACE activation in vivo, we used tissue inhibitor of metalloproteinase 3 (Timp3) null mice, because Timp3 is the specific inhibitor of TACE and Timp3(-/-) mice have higher TACE activity compared with wild-type (WT) mice. Timp3(-/-) mice fed a HFD for 5 months are glucose-intolerant and insulin-resistant; they showed macrovesicular steatosis and ballooning degeneration compared with WT mice, which presented only microvesicular steatosis. Shotgun proteomics analysis revealed that Timp3(-/-) liver showed a significant differential expression of 38 proteins, including lower levels of adenosine kinase, methionine adenosysltransferase I/III, and glycine N-methyltransferase and higher levels of liver fatty acid-binding protein 1. These changes in protein levels were also observed in hepatocytes infected with adenovirus encoding TACE. All these proteins play a role in fatty acid uptake, triglyceride synthesis, and methionine metabolism, providing a molecular explanation for the increased hepatosteatosis observed in Timp3(-/-) compared with WT mice. CONCLUSION: We have identified novel mechanisms, governed by the TACE-Timp3 interaction, involved in the determination of insulin resistance and liver steatosis during overfeeding in mice.

Characterization of the endocannabinoid system in human neuronal cells and proteomic analysis of anandamide-induced apoptosis.

Anandamide (AEA) is an endogenous agonist of type 1 cannabinoid receptors (CB1R) that, along with metabolic enzymes of AEA and congeners, compose the "endocannabinoid system." Here we report the biochemical, morphological, and functional characterization of the endocannabinoid system in human neuroblastoma SH-SY5Y cells that are an experimental model for neuronal cell damage and death, as well as for major human neurodegenerative disorders. We also show that AEA dose-dependently induced apoptosis of SH-SY5Y cells. Through proteomic analysis, we further demonstrate that AEA-induced apoptosis was paralleled by an approximately 3 to approximately 5-fold up-regulation or down-regulation of five genes; IgG heavy chain-binding protein, stress-induced phosphoprotein-1, and triose-phosphate isomerase-1, which were up-regulated, are known to act as anti-apoptotic agents; actin-related protein 2/3 complex subunit 5 and peptidylprolyl isomerase-like protein 3 isoform PPIL3b were down-regulated, and the first is required for actin network formation whereas the second is still function-orphan. Interestingly, only the effect of AEA on BiP was reversed by the CB1R antagonist SR141716, in SH-SY5Y cells as well as in human neuroblastoma LAN-5 cells (that express a functional CB1R) but not in SK-NBE cells (which do not express CB1R). Silencing or overexpression of BiP increased or reduced, respectively, AEA-induced apoptosis of SH-SY5Y cells. In addition, the expression of BiP and of the BiP-related apoptotic markers p53 and PUMA was increased by AEA through a CB1R-dependent pathway that engages p38 and p42/44 mitogen-activated protein kinases. Consistently, this effect of AEA was minimized by SR141716. In conclusion, we identified BiP as a key protein in neuronal apoptosis induced by AEA.

Tissue inhibitor of metalloproteinase 3 deficiency causes hepatic steatosis and adipose tissue inflammation in mice.

BACKGROUND & AIMS: Obesity-driven, low-grade inflammation affects systemic metabolic function and can lead to insulin resistance, hepatic steatosis, and atherosclerosis. Decreased expression of tissue inhibitor of metalloproteinase 3 (Timp3) is a catalyst for insulin resistance and inflammation. Timp3 is a natural inhibitor of matrix metalloproteinases, tumor necrosis factor-alpha-converting enzyme (TACE), and vascular endothelial growth factor receptor 2, and therefore could affect signaling processes involved in inflammation and angiogenesis. METHODS: We assessed the effects of Timp3 on inflammation, tissue remodeling, and intermediary metabolism in mice, under conditions of environmental stress (high-fat diet), genetic predisposition to insulin resistance (insulin receptor [Insr] haploinsufficiency), and varying levels of inflammation (Timp3 or Tace deficiencies). Metabolic tests, immunohistochemistry, real-time polymerase chain reaction, and immunoblotting were used to compare data from wild-type, Insr(+/-), Timp3(-/-), Insr(+/-)Timp3(-/-), and Insr(+/-)Tace(+/-) mice placed on high-fat diets for 10 weeks. RESULTS: Insr(+/-)Timp3(-/-) mice showed a higher degree of adipose and hepatic inflammation compared with wild-type, Insr(+/-), Timp3(-/-), and Insr(+/-)Tace(+/-) mice. In particular, the Insr(+/-)Timp3(-/-) mice developed macrovesicular steatosis and features of severe nonalcoholic fatty liver disease, including lobular and periportal inflammation, hepatocellular ballooning, and perisinusoidal fibrosis. These were associated with increased expression of inflammatory and steatosis markers, including suppressor of cytokine signaling 3 and stearoyl CoA desaturase 1, in both liver and adipose tissue. Interestingly, Insr(+/-)Tace(+/-) mice had a nearly opposite phenotype. CONCLUSIONS: Timp3, possibly through its regulation of TACE, appears to have a role in the pathogenesis of fatty liver disease associated with obesity.

Proteomic investigation in A549 lung cell line stably infected by HPV16E6/E7 oncogenes.

BACKGROUND: Data have accumulated implicating the involvement of oncogenic human papillomaviruses (HPVs) in bronchial carcinogenesis. We recently described the presence of oncogenic HPV transcripts in non-small cell lung cancers. OBJECTIVE: To investigate the role of oncogenic HPVs in lung carcinogenesis. MATERIAL AND METHODS: The lung cell line A549 stably infected with HPV16E6, HPV16E7 and HPVE6/E7 constructs was used to investigate the protein profile changes associated with the expression of these oncogenes. Replicated two-dimensional gel electrophoresis gels from uninfected and stably HPV16E6-, E7-, and E6/E7-infected A549 cells were compared for changes in protein profile. Protein identification was achieved by peptide mass fingerprinting by MALDI-TOF-MS and nLC-ESI-Q-TOF-MS/MS peptide ladder sequencing. RESULTS: We identified 17 different polypeptides whose average normalized spot intensity was statistically significant (p < 0.05) and differed by 2-fold. Relationships between differentially expressed proteins and the HPV-induced infection mechanism have been clustered by knowledge-base database functional association network analysis. CONCLUSION: The impact of Hsp27, annexin III, annexin IV, Gp96 and TPT1 on the cellular response mechanism to HPV infection is presented and discussed.

CD28 delivers a unique signal leading to the selective recruitment of RelA and p52 NF-kappaB subunits on IL-8 and Bcl-xL gene promoters.

CD28 is one of the most important costimulatory receptors necessary for full T lymphocyte activation. The CD28 receptor can enhance T cell antigen receptor (TCR) signals, as well as deliver independent signals. Indeed, CD28 engagement by B7 can generate TCR-independent signals leading to IkappaB kinase and NF-kappaB activation. Here we demonstrate that the TCR-independent CD28 signal leads to the selective transcription of survival (Bcl-xL) and inflammatory (IL-8 and B cell activation factor, but not proliferative (IL-2), genes, in a NF-kappaB-dependent manner. CD28-stimulated T cells actively secrete IL-8, and Bcl-xL up-regulation protects T cells from radiation-induced apoptosis. The transcription of CD28-induced genes is mediated by the specific recruitment of RelA and p52 NF-kappaB subunits to target promoters. In contrast, p50 and c-Rel, which preferentially bind NF-kappaB sites on the IL-2 gene promoter after anti-CD3 stimulation, are not involved. Thus, we identify CD28 as a key regulator of genes important for both survival and inflammation.