Efficacy of transarterial chemoembolization compared with radiofrequency ablation for the treatment of recurrent hepatocellular carcinoma after radiofrequency ablation.

Purpose: To compare the efficacy and outcome of transarterial chemoembolization (TACE) with radiofrequency ablation (RFA) in the treatment of recurrent hepatocellular carcinoma (HCC) after initial RFA.Material and methods: From January 2008 to December 2014, 199 consecutive patients with primary HCC underwent percutaneous RFA as initial treatment. One hundred and fourteen patients developed intrahepatic recurrent HCC after initial RFA. The patients with recurrent tumor size ≤3 cm and tumor numbers ≤3 who underwent RFA (n = 47) or TACE (n = 31) were included in study. Progression-free survival (PFS), tumor response to treatment and overall survival (OS) were assessed. Prognostic factors for OS were analyzed using multivariate Cox proportional hazard models.Results: The baseline data of initial HCC and the first recurrence of HCC were comparable in both groups. The complete response (CR) rate in the RFA group and the TACE group was 95.7% and 50%, respectively (p < .001). The PFS time in the RFA group and the TACE group was 424 days and 275 days, respectively (p = .004). The one-year and three-year cumulative overall survival rate was 93.5% and 45% in the TACE group, 91.3% and 68.8% in the RFA group (p = .49), respectively. Significant predictive factors for OS were tumor size (HR = 1.951, 95%CI 1.061-3.687, p = .032), prothrombin time (HR = 1.59, 95%CI 1.012-2.498, p = .044) and response to treatment (HR = 0.267, 95%CI 0.092-0.78, p = .016).Conclusion: Repeated RFA is still considered to be the first treatment choice for patients with post-RFA intrahepatic recurrence. However, TACE should also be considered due to comparable overall survival benefits. The advantages of being less invasive and highly repeatable may render TACE to be a preferred treatment for some patients with recurrent HCC after RFA.

Highly Conducting Surface-Silverized Aromatic Polysulfonamide (PSA) Fibers with Excellent Performance Prepared by Nano-Electroplating.

In this work, bilayer nanocoatings were designed and constructed on high-performance aromatic polysulfonamide (PSA) fibers for robust electric conduction and electromagnetic interference (EMI) shielding. More specifically, PSA fibers were first endowed with necessary electric conductivity via electroless nickel (Ni) or nickel alloy (Ni-P-B) plating. Afterward, silver electroplating was carried out to further improve the performance of the composite. The morphology, microstructure, environmental stability, mechanical properties, and EMI shielding performance of the proposed cladded fibers were thoroughly investigated to examine the effects of electrodeposition on both amorphous Ni-P-B and crystalline Ni substrates. The acquired results demonstrated that both PSA@Ni@Ag and PSA@Ni-P-B@Ag composite fibers had high environment stability, good tensile strength, low electric resistance, and outstanding EMI shielding efficiency. This indicates that they can have wide application prospects in aviation, aerospace, telecommunications, and military industries. Furthermore, the PSA@Ni-P-B@Ag fiber configuration seemed more reasonable because it exhibited smoother and denser silver surfaces as well as stronger interfacial binding, leading to lower resistance (185 mΩ cm-1) and better shielding efficiency (82.48 dB in the X-band).

Fabrication of highly conductive, flexible, and hydrophobic Kevlar®@Ni-P-B@Cu@CS fabric with excellent self-cleaning performance for electromagnetic interference shielding.

In this work, a simple and cost-effective method was proposed and developed to prepare a novel multilayer-structured Kevlar®@nickel-phosphorus-boron@copper@copper stearate (Kevlar®@Ni-P-B@Cu@CS) composite fabric with high conductivity, high flexibility, high hydrophobicity, and high durability to effectively shield electromagnetic interference (EMI). In this method, an amorphous Ni-P-B alloy nanolayer was initially deposited onto a Kevlar® fabric via electroless plating. Afterward, a crystalline Cu nanolayer was deposited as the second layer via electroplating. Finally, a monolayer of copper stearate was innovatively self-assembled as the outermost protective layer. The Cu deposition was effectively adjusted and designed by controlling the plating current and plating time. The electrical resistance and contact angle of the optimized Kevlar®@Ni-P-B@Cu@CS composite fabric were as low as 3.2 mΩ sq-1 and as high as 115.39°, respectively, indicating that the fabric could withstand bending, tape-off, corrosion, and accelerated environmental tests. The average EMI-shielding efficiency of the durable composite fabric was 93.9 dB in the frequency range of 8.2-12.4 GHz, which was mainly attributed to the absorption loss. Thus, the proposed material configuration has promise for applications in aviation, aerospace, telecommunication, wearable devices, and military industries.

Predictive value of PET metabolic parameters for occult lymph node metastases in PET/CT defined node-negative patients with advanced epithelial ovarian cancer.

Accurate lymph node metastasis (LNM) prediction is crucial for patients with advanced epithelial ovarian cancer (AEOC) since it guides the decisions about lymphadenectomy. Previous studies have shown that occult lymph node metastasis (OLNM) is common in AEOC. The objective of our study is to quantitatively assess the probability of occult lymph node metastasis defined by 18F-Fluorodeoxyglucose PET/CT in AEOC and explore relationship between OLNM and PET metabolic parameters. The patients with pathologically confirmed AEOC who underwent PET/CT for preoperative staging at our institute were reviewed. Univariate and multivariate analysis were performed to evaluate the predictive value of PET/CT-related metabolic parameters for OLNM. The result of our study showed metastatic TLG index had a better diagnostic performance than other PET/CT-related metabolic parameters. Two variables were independently and significantly associated with OLNM in multivariate analysis: metastatic TLG index and primary tumor location. The logistic model combining metastatic TLG index, primary tumor location, and CA125 might be a promising tool to effectively predict the individualized possibility of OLNM for AEOC patients.

Three trocars laparoscopic abdominal aortic aneurysm repair.

Total laparoscopic abdominal aortic aneurysm resection with tube graft interposition was performed in a 53-year-old woman diagnosed with an infrarenal abdominal aortic aneurysm. The operation was accomplished by a method using three trocars. The operation took 240 minutes. Blood loss was 600 mL. No complications occurred in 13 months of postoperative follow-up. These results show that total laparoscopic abdominal aortic aneurysm repair with three trocars is feasible and worthwhile.

Confocal microscopy for modeling electron microbeam irradiation of skin.

For radiation exposures employing targeted sources such as particle microbeams, the deposition of energy and dose will depend on the spatial heterogeneity of the sample. Although cell structural variations are relatively minor for two-dimensional cell cultures, they can vary significantly for fully differentiated tissues. Employing high-resolution confocal microscopy, we have determined the spatial distribution, size, and shape of epidermal keratinocyte nuclei for the full-thickness EpiDerm™ skin model (MatTek, Ashland, VA). Application of these data to calculate the microdosimetry and microdistribution of energy deposition by an electron microbeam is discussed.

Radiomics Analysis of PET and CT Components of 18F-FDG PET/CT Imaging for Prediction of Progression-Free Survival in Advanced High-Grade Serous Ovarian Cancer.

OBJECTIVE: To investigate radiomics features extracted from PET and CT components of 18F-FDG PET/CT images integrating clinical factors and metabolic parameters of PET to predict progression-free survival (PFS) in advanced high-grade serous ovarian cancer (HGSOC). METHODS: A total of 261 patients were finally enrolled in this study and randomly divided into training (n=182) and validation cohorts (n=79). The data of clinical features and metabolic parameters of PET were reviewed from hospital information system(HIS). All volumes of interest (VOIs) of PET/CT images were semi-automatically segmented with a threshold of 42% of maximal standard uptake value (SUVmax) in PET images. A total of 1700 (850×2) radiomics features were separately extracted from PET and CT components of PET/CT images. Then two radiomics signatures (RSs) were constructed by the least absolute shrinkage and selection operator (LASSO) method. The RSs of PET (PET_RS) and CT components(CT_RS) were separately divided into low and high RS groups according to the optimum cutoff value. The potential associations between RSs with PFS were assessed in training and validation cohorts based on the Log-rank test. Clinical features and metabolic parameters of PET images (PET_MP) with P-value <0.05 in univariate and multivariate Cox regression were combined with PET_RS and CT_RS to develop prediction nomograms (Clinical, Clinical+ PET_MP, Clinical+ PET_RS, Clinical+ CT_RS, Clinical+ PET_MP + PET_RS, Clinical+ PET_MP + CT_RS) by using multivariate Cox regression. The concordance index (C-index), calibration curve, and net reclassification improvement (NRI) was applied to evaluate the predictive performance of nomograms in training and validation cohorts. RESULTS: In univariate Cox regression analysis, six clinical features were significantly associated with PFS. Ten PET radiomics features were selected by LASSO to construct PET_RS, and 1 CT radiomics features to construct CT_RS. PET_RS and CT_RS was significantly associated with PFS both in training (P <0.00 for both RSs) and validation cohorts (P=0.01 for both RSs). Because there was no PET_MP significantly associated with PFS in training cohorts. Only three models were constructed by 4 clinical features with P-value <0.05 in multivariate Cox regression and RSs (Clinical, Clinical+ PET_RS, Clinical+ CT_RS). Clinical+ PET_RS model showed higher prognostic performance than other models in training cohort (C-index=0.70, 95% CI 0.68-0.72) and validation cohort (C-index=0.70, 95% CI 0.66-0.74). Calibration curves of each model for prediction of 1-, 3-year PFS indicated Clinical +PET_RS model showed excellent agreements between estimated and the observed 1-, 3-outcomes. Compared to the basic clinical model, Clinical+ PET_MS model resulted in greater improvement in predictive performance in the validation cohort. CONCLUSION: PET_RS can improve diagnostic accuracy and provide complementary prognostic information compared with the use of clinical factors alone or combined with CT_RS. The newly developed radiomics nomogram is an effective tool to predict PFS for patients with advanced HGSOC.

Cardiac-targeted expression of soluble fas attenuates doxorubicin-induced cardiotoxicity in mice.

Doxorubicin (Dox) is known to cause cardiomyopathy and congestive heart failure upon chronic administration. The mechanisms underlying these toxicities remain uncertain but have been attributed, at least in part, by induction of cardiac cell apoptosis. Fas ligation with its cognate ligand (FasL) induces apoptosis and activates cellular inflammatory responses associated with tissue injury. We determined whether interruption of Fas/FasL interaction by cardiac-targeted expression of soluble Fas (sFas), a competitive inhibitor of FasL, would protect against Dox chronic cardiotoxicity in mice. Wild-type (WT) and sFas transgenic mice were administrated intravenously with 4 mg/kg Dox or with an equivalent volume of saline twice a week for a total of 10 injections. There were 25% mortality in WT mice, but no death was observed in sFas mice during the period of Dox treatment. Echocardiographic evaluation revealed a significant decrease in left ventricle fractional shortening after Dox treatment in WT mice but not in sFas mice. WT mice treated with Dox developed extensive myocardial cytoplasmic vacuolization, apoptosis, and interstitial fibrosis, which were much less or absent in sFas mice. The increased inducible nitric oxide synthase expression, nitric oxide production, superoxide generation, and peroxynitrite formation after Dox treatment in WT mice were attenuated by sFas expression. sFas expression also attenuated Dox-mediated induction of proinflammatory cytokines, tumor necrosis factor-alpha, interleukin (IL)-1beta, and IL-6 in the myocardium. These observations indicate that FasL is an important mediator in Dox-associated cardiotoxicity by generating reactive oxygen and nitrogen species.

Radiomics Signatures of Computed Tomography Imaging for Predicting Risk Categorization and Clinical Stage of Thymomas.

PURPOSE: The aim of this study is to develop and compare performance of radiomics signatures using texture features extracted from noncontrast enhanced CT (NECT) and contrast enhanced CT (CECT) images for preoperative predicting risk categorization and clinical stage of thymomas. MATERIALS AND METHODS: Between January 2010 and October 2018, 199 patients with surgical resection and histopathologically confirmed thymoma were enrolled in this retrospective study. We extracted 841 radiomics features separately from volume of interest (VOI) in NECT and CECT images. The features with poor reproducibility and highly redundancy were removed. Then a least absolute shrinkage and selection operator method (LASSO) logistic regression model with 10-fold cross validation was used for further feature selection and radiomics signatures build. The predictive performances of radiomics signatures were assessed by receiver operating characteristic (ROC) analysis. The areas under the receiver operating characteristic curve (AUC) between radiomics signatures were compared by using Delong test. RESULT: In differentiating high risk thymomas from low risk thymomas, the AUC, sensitivity, and specificity were 0.801(95% CI 0.740-0.863), 0.752 and 0.767 for radiomics signature based on NECT images, and 0.827 (95% CI 0.771 -0.884), 0.798, and 0.722 for radiomics signature based on CECT images. But there was no significant difference (p=0.365) between them. In differentiating advanced stage thymomas from early stage thymomas, the AUC, sensitivity, and specificity were 0.829 (95%CI 0.757-0.900), 0.712, and 0.806 for radiomics signature based on NECT images and 0.860 (95%CI 0.803-0.917), 0.699, and 0.889 for radiomics signature based on CECT images. There was no significant difference (p=0.069) between them. The accuracy was 0.819 for radiomics signature based on NECT images, 0.869 for radiomics signature based on CECT images, and 0.779 for radiologists. Both radiomics signatures had a better performance than radiologists. But there was significant difference (p = 0.025) only between CECT radiomics signature and radiologists. CONCLUSION: Radiomics signatures based on texture analysis from NECT and CECT images could be utilized as noninvasive biomarkers for differentiating high risk thymomas from low risk thymomas and advanced stage thymomas from early stage thymoma. As a quantitative method, radiomics signature can provide complementary diagnostic information and help to plan personalized treatment for patients with thymomas.

Neural control of substance P induced up-regulation and release of macrophage migration inhibitory factor in the rat bladder.

PURPOSE: Macrophage migration inhibitory factor is increased in intraluminal fluid after experimental inflammation and it mediates proinflammatory effects on the bladder. We examined the contribution of nerve activity and specific neurotransmitter systems to the mechanism of macrophage migration inhibitory factor release from the bladder during inflammation. MATERIALS AND METHODS: Male Sprague-Dawley rats were anesthetized. The bladders were emptied and filled with saline. Rats received saline as a control (0.1 ml/100 gm body weight) or substance P (Sigma) (40 microg/kg in saline, 0.1 ml/100 gm body weight) subcutaneously as well as hexamethonium (Sigma) (50 mg/kg) intraperitoneally in saline (0.1 ml/100 gm body weight), lidocaine (2%, 0.3 ml) intravesically, atropine (Sigma) (3 mg/kg in saline, 0.1 ml/100 gm body weight) intravenously, propranolol (Sigma) (3 mg/kg in saline, 0.1 ml/100 gm body weight) intravenously or phentolamine (Sigma) (10 mg/kg in saline, 0.1 ml/100 gm body weight) intravenously. After 1 hour the intravesical fluid was removed and the bladder was excised. Macrophage migration inhibitory factor levels in intraluminal fluid were measured by enzyme-linked immunosorbent assay and Western blotting. MIF expression in bladder homogenates was examined using reverse transcriptase-polymerase chain reaction. RESULTS: Intravesical lidocaine or ganglionic blockage with hexamethonium prevented substance P induced macrophage migration inhibitory factor release. In addition, pretreatment with atropine and phentolamine but not propranolol also prevented macrophage migration inhibitory factor release. While MIF up-regulation in the bladder was increased with substance P treatment, it was only prevented by intravesical lidocaine. CONCLUSIONS: Substance P induced macrophage migration inhibitory factor release in the bladder is mediated through nerve activation. Postganglionic parasympathetic (via muscarinic receptors) and sympathetic (via alpha-adrenergic receptors) fibers mediate macrophage migration inhibitory factor release, while activating bladder afferent nerve terminals up-regulates MIF.

Upregulation of macrophage migration inhibitory factor (MIF) and CD74, receptor for MIF, in rat bladder during persistent cyclophosphamide-induced inflammation.

The objective of this study was to determine if macrophage migration inhibitory factor (MIF) is upregulated in the bladder during persistent cystitis. MIF is a pro-inflammatory cytokine found pre-formed in the urothelium. Previous findings showed that acute bladder inflammation increased MIF release into the bladder lumen while upregulating MIF and CD74 (MIF receptor) in the bladder. Because the effects of persistent cystitis on MIF and CD74 are not known, MIF and CD74 changes in the bladder were examined after short-term (1-day) or persistent (8-day) cyclophosphamide (CYP)-induced bladder inflammation. Anesthetized male Sprague-Dawley rats received either a single CYP treatment (150 mg/kg, ip; saline, control) and examined 1 day after treatment (short-term), or repeated CYP doses (20-75 mg/ kg, ip; saline, control; every third day for 8 days) and examined after 8 days of treatment (persistent). MIF protein levels in urine and bladder were determined. In addition, Mif, CD74, and cox-2 expression in the bladder was determined. Histology verified cystitis and MIF and CD74 immunoreactivity in the bladder. Repeated CYP doses were decreased to avoid toxicity. Short-term or repeated low CYP doses (40 mg/kg; 8 days) increased urinary MIF and decreased bladder MIF amounts while upregulating bladder Mif and CD74 mRNA expression. Persistent CYP-induced bladder inflammation (even at 40 mg/kg; 8-day treatment) also upregulated other inflammatory cytokines (CCL5, IL-11, iNOS) in the bladder. Short-term and persistent (low dose) CYP cystitis are associated with markedly increased MIF release into the urine and upregulation of Mif and CD74 in bladder. This supports the hypothesis that MIF and CD74 play a significant role in both acute and persistent stages of bladder inflammation.

Cardioprotective effects of cerium oxide nanoparticles in a transgenic murine model of cardiomyopathy.

OBJECTIVE: Cerium oxide (CeO2) nanoparticles have been shown to protect cells in culture from lethal stress, but no protection in vivo has been reported. Cardiac-specific expression of monocyte chemoattractant protein (MCP)-1 in mice causes ischemic cardiomyopathy associated with activation of endoplasmic reticulum (ER) stress. The aim of this study was to assess the effects of CeO2 nanoparticles on cardiac function and remodeling as well as ER stress response in this murine model of cardiomyopathy. METHODS: MCP-1 transgenic mice (MCP mice) and wild-type controls were administered intravenously 15 nmol of CeO2 nanoparticles or vehicle only twice a week for 2 weeks. Cardiac function, myocardial histology, nitrotyrosine formation, expression of cytokines, and ER stress-associated genes were evaluated. RESULTS: Treatment with CeO2 nanoparticles markedly inhibited progressive left ventricular dysfunction and dilatation in MCP mice and caused a significant decrease in serum levels of MCP-1, C-reactive protein, and total nitrated proteins. The infiltration of monocytes/macrophages, accumulation of 3-nitrotyrosine, apoptotic cell death, and expression of proinflammatory cytokines, tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, and IL-6 in the myocardium were markedly inhibited by CeO2 nanoparticles. Expression of the key ER stress-associated genes, including glucose-regulated protein 78 (Grp78), protein disulfide isomerase (PDI), and heat shock proteins (HSP25, HSP40, HSP70), were also suppressed by CeO2 nanoparticles. CONCLUSIONS: CeO2 nanoparticles protect against the progression of cardiac dysfunction and remodeling by attenuation of myocardial oxidative stress, ER stress, and inflammatory processes probably through their autoregenerative antioxidant properties.

Factors affecting the accuracy and safety of computed tomography-guided biopsy of intrapulmonary solitary nodules ≤30 mm in a retrospective study of 155 patients.

Computed tomography (CT)-guided percutaneous fine needle biopsy is a common method for lung biopsy. The objective of this study was to investigate factors affecting the accuracy and safety of CT-guided percutaneous lung biopsy of nodules ≤30 mm in diameter. Between January 2013 and March 2014, 155 patients underwent a CT-guided percutaneous biopsy procedure on an intrapulmonary solitary nodule measuring ≤30 mm in diameter. Prospectively collected data were retrospectively reviewed and examined for the influence of clinical and pathological characteristics (age, gender, smoking status, adhesion of nodule to the pleura, puncture depth, nodule size and time of biopsy) on the accuracy of biopsy and incidence of pneumothorax and hemorrhage. The accuracy of CT-guided biopsy was 90.3% (140/155). Biopsies predominantly contained lung adenocarcinoma (114/140; 81.4%) or squamous cell carcinoma of the lung (10/140; 7.1%). Accuracy was significantly dependent on nodule size, ranging in accuracy from 85 to 97% for patients with nodule diameters of ≤20 or 21-30 mm, respectively (P<0.05). Pleural adherence of the nodule significantly increased the accuracy of the biopsy (P<0.05). Patients with a nodule of 11-20 mm in diameter had a significantly higher incidence of pneumothorax compared with patients with a smaller nodule (P=0.013). In conclusion, the nodule size and adhesion to the pleura influenced the accuracy of CT-guided biopsy of intrapulmonary nodules that were ≤30 mm in diameter. Nodule size may also affect the incidence of severe complications. CT-guided percutaneous lung biopsy has a high accuracy and is easy and safe to conduct for intrapulmonary solitary nodules of ≤30 mm in diameter.

Sequential Use of Transhepatic Arterial Chemoembolization and Bipolar Radiofrequency Ablation in the Clinical Therapy of Hepatocellular Carcinoma.

This retrospective study investigated the clinical application of sequential therapy with transarterial chemoembolization (TACE) and CT-guided radiofrequency ablation (RFA) using a bipolar needle in treating hepatocellular carcinoma (HCC) tumors of different sizes. The study included patients (N = 46) with HCC from Shengjing Hospital of China Medical University who had received TACE and RFA from November 2012 to November 2013. Eligible patients had an Eastern Cooperative Oncology Group (ECOG) score of 0-1, a Child-Pugh grade of A-B, and no contradictions for TACE and/or RFA. Fifty one hepatic lesions of varying sizes were treated with TACE followed by RFA. Clinical response and 1- and 2-year survival rates were assessed. The frequency of complete and incomplete ablation following therapy was significantly different across the varying RFA pin numbers and the maximum diameter of the lesion (p ≤ 0.001). A greater percentage (97.3%) of lesions that were ≤3 cm in diameter were completely ablated compared with lesions that were 3-5 cm (88.9%) and >5 cm in diameter (20%). The median survival time of patients was 16.5 months, and the 1- and 2-year survival rates were 95.7% and 69.3%, respectively. There were only a limited number of complications, all of which were minor. These included hemothorax (4.3%), abdominal hemorrhage (10.9%), and abdominal hemorrhage with minor pneumothorax (2.2%). This study found that the sequential treatment with TACE and CT-guided RFA using a bipolar needle is effective and well tolerated in patients with HCC and that the effectiveness of treatment is dependent on tumor size.

Carcinogenic and inflammatory effects of plutonium-nitrate retention in an exposed nuclear worker and beagle dogs.

PURPOSE: Plutonium-nitrate has a moderately rapid translocation rate from the lung to blood stream. Previous studies have shown an unexpected retention of soluble plutonium in the beagles and human case studied here. The inflammatory responses that may be associated with long-term exposure to ionizing radiation were characterized. These pathways include tissue injury, apoptosis, and gene expression modifications. Other protein modifications related to carcinogenesis and inflammation and the various factors that may play a role in orchestrating complex interactions which influence tissue integrity following irradiation were investigated. MATERIALS AND METHODS: We have examined numerous lung samples from a plutonium-exposed worker, a human control, and a variety of plutonium-exposed beagle dogs using immunohistochemistry and quantitative Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR). RESULTS: The exposed human showed interstitial fibrosis in peripheral regions of the lung, but no pulmonary tumors. Beagles with similar doses were diagnosed with tumors in bronchiolo-alveolar, peripheral and sub-pleural alveolar regions of the lung. The terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay showed an elevation of apoptosis in tracheal mucosa, tumor cells, and nuclear debris in the alveoli and lymph nodes of the beagles but not in the human case. In both the beagles and human there were statistically significant modifications in the expression of Fas ligand (FASLG), B-cell lymphoma 2 (BCL2), and Caspase 3 (CASP3). CONCLUSIONS: The data suggests that FASLG, BCL2, CASP3 and apoptosis play a role in the inflammatory responses following prolonged plutonium exposure. Utilizing these unique tissues revealed which pathways are triggered following the internal deposition and long-term retention of plutonium-nitrate in a human and a large animal model.

Cell type-dependent gene transcription profile in a three-dimensional human skin tissue model exposed to low doses of ionizing radiation: implications for medical exposures.

The concern over possible health risks from exposures to low doses of ionizing radiation has been driven largely by the increase in medical exposures, the routine implementation of X-ray backscatter devices for airport security screening, and, most recently, the nuclear incident in Japan. Because of a paucity of direct epidemiological data at very low doses, cancer risk must be estimated from high dose exposure scenarios. However, there is increasing evidence that low and high dose exposures result in different signaling events and may have different response mechanisms than higher doses. We have examined the radiation-induced temporal response after exposure to 10 cGy of an in vitro three dimensional (3D) human skin tissue model using microarray-based transcriptional profiling. Cell type-specific analysis showed significant changes in gene expression with the levels of >1,400 genes altered in the dermis and >400 genes regulated in the epidermis. The two cell layers rarely exhibited overlapping responses at the mRNA level. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) measurements validated the microarray data in both regulation direction and value. Key pathways identified relate to cell cycle regulation, immune responses, hypoxia, reactive oxygen signaling, and DNA damage repair. The proliferation status as well as the expression of PCNA was examined in histological samples. We discuss in particular the role of proliferation, emphasizing how the disregulation of cellular signaling in normal tissue may impact progression toward radiation-induced secondary diseases.

Intraluminal blockade of cell-surface CD74 and glucose regulated protein 78 prevents substance P-induced bladder inflammatory changes in the rat.

BACKGROUND: Macrophage migration inhibitory factor (MIF) is a pro-inflammatory cytokine constitutively expressed by urothelial cells. During inflammatory stimuli, MIF is released into the lumen complexed to other proteins and these complexes can bind to urothelial cell-surface receptors to activate signaling pathways. Since MIF is complexed to alpha1-inhibitor III (A1-I3; a member of the alpha2-macroglubulin family) and glucose regulated protein 78 (GRP78) is a receptor for A1-I3 the goals of this study were to determine if substance P elicits urothelial cell-surface expression of GRP78 and to assess the functional role of CD74 (receptor for MIF) or GRP78 in substance P-induced bladder inflammatory changes. METHODOLOGY/PRINCIPAL FINDINGS: Anesthetized male Sprague-Dawley rats received either saline or substance P (s.c.), bladders were collected 1 hour after treatment and processed for histology or protein/mRNA. The expression of GRP78 at urothelial cell-surface was determined by performing in vivo biotinylation of urothelial cell-surface proteins. Finally, in order to determine the effects of receptor blockade on substance P-induced MIF release and inflammatory changes, rats received either intraluminal antibodies to CD74, GRP78, both, or non-specific IgG (as a control). GRP78 and MIF immunostaining was simultaneously visualized in umbrella cells only after substance P treatment. Immunoprecipitation studies showed GRP78-MIF complexes increased after substance P while in vivo biotinylation confirmed substance P-induced GRP78 cell-surface expression in urothelial cells. Intraluminal blockade of CD74 and/or GRP78 prevented substance P-induced changes, including bladder edema, intraluminal MIF release by urothelial cells and production of inflammatory cytokines by urothelial cells. CONCLUSIONS/SIGNIFICANCE: GRP78 is expressed on the surface of urothelial cells after substance P treatment where it can bind MIF complexes. Blocking CD74 (receptor for MIF) and/or GRP78 prevented substance P-induced inflammatory changes in bladder and urothelium, indicating that these urothelial receptors are effective targets for disrupting MIF-mediated bladder inflammation.

Cyclophosphamide-induced cystitis increases bladder CXCR4 expression and CXCR4-macrophage migration inhibitory factor association.

BACKGROUND: Macrophage migration inhibitory factor (MIF) is a pro-inflammatory cytokine involved in cystitis and a non-cognate ligand of the chemokine receptor CXCR4 in vitro. We studied whether CXCR4-MIF associations occur in rat bladder and the effect of experimental cystitis. METHODS AND FINDINGS: Twenty male rats received saline or cyclophosphamide (40 mg/kg; i.p.; every 3(rd) day) to induce persistent cystitis. After eight days, urine was collected and bladders excised under anesthesia. Bladder CXCR4 and CXCR4-MIF co-localization were examined with immunhistochemistry. ELISA determined MIF and stromal derived factor-1 (SDF-1; cognate ligand for CXCR4) levels. Bladder CXCR4 expression (real-time RTC-PCR) and protein levels (Western blotting) were examined. Co-immunoprecipitations studied MIF-CXCR4 associations.Urothelial basal and intermediate (but not superficial) cells in saline-treated rats contained CXCR4, co-localized with MIF. Cyclophosphamide treatment caused: 1) significant redistribution of CXCR4 immunostaining to all urothelial layers (especially apical surface of superficial cells) and increased bladder CXCR4 expression; 2) increased urine MIF with decreased bladder MIF; 3) increased bladder SDF-1; 4) increased CXCR4-MIF associations. CONCLUSIONS: These data demonstrate CXCR4-MIF associations occur in vivo in rat bladder and increase in experimental cystitis. Thus, CXCR4 represents an alternative pathway for MIF-mediated signal transduction during bladder inflammation. In the bladder, MIF may compete with SDF-1 (cognate ligand) to activate signal transduction mediated by CXCR4.