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Nitrative and oxidative DNA damage plays an important role in inflammation-related carcinogenesis. To investigate the involvement of stem cells in Epstein-Barr virus infection-related nasopharyngeal carcinoma (NPC), we used double immunofluorescence staining to examine several cancer stem/progenitor cell markers (CD44v6, CD24, and ALDH1A1) in NPC tissues and NPC cell lines. We also measured 8-nitroguanine formation as an indicator of inflammation-related DNA lesions. The staining intensity of 8-nitroguanine was significantly higher in cancer cells and inflammatory cells in the stroma of NPC tissues than in chronic nasopharyngitis tissues. Expression levels of CD44v6 and ALDH1A1 were significantly increased in cancer cells of primary NPC specimens in comparison to chronic nasopharyngitis tissues. Similarly, more intense staining of CD44v6 and ALDH1A1 was detected in an NPC cell line than in an immortalized nasopharyngeal epithelial cell line. In the case of CD24 staining, there was no significant difference between NPC and chronic nasopharyngitis tissues. 8-Nitroguanine was detected in both CD44v6- and ALDH1A1-positive stem cells in NPC tissues. In conclusion, CD44v6 and ALDH1A1 are candidate stem cell markers for NPC, and the increased formation of DNA lesions by inflammation may result in the mutation of stem cells, leading to tumor development in NPC.

Puerarin is an isoflavonoid isolated from the root of the plant Pueraria lobata and has been used as a prescribed drug in China for the treatment of many diseases in the clinical practice. The present study aimed to determine the protective effects and the underlying mechanisms of puerarin on ovalbumin (OVA)-induced allergic inflammation in a mouse model of allergic asthma. Asthma mice model was established by ovalbumin. A total of 50 mice were randomly assigned to five experimental groups: control, model, dexamethasone (2 mg/kg), and puerarin (10 mg/kg, 20 mg/kg). Airway resistance (Raw) was measured by the forced oscillation technique, differential cell count in BAL fluid (BALF) was measured by Wright-Giemsa staining, histological assessment was measured by hematoxylin and eosin (HE) staining, BALF levels of Th1/Th2 cytokines were measured by enzyme-linked immunosorbent assay, eotaxin-3 was evaluated by western blotting. Our study demonstrated that, compared with model group, puerarin inhibited OVA-induced increases in Raw and eosinophil count; interleukin (IL)-4, IL-5, IL-13 levels were recovered in bronchoalveolar lavage fluid compared; increased IFN-γ level in bronchoalveolar lavage fluid; histological studies demonstrated that puerarin substantially inhibited OVA-induced eosinophilia in lung tissue compared with model group. Western blotting studies demonstrated that puerarin substantially inhibited eotaxin-3 compared with model group. Our findings support puerarin can prevent some signs of allergic asthma in the mouse model., (Copyright © 2015. Published by Elsevier B.V.)

Background and Purpose: Notch1 activation mediated by γ-secretase is critical for angiogenesis. GeneCards database predicted that Caspase-4 (CASP4, with murine ortholog CASP11) interacts with presenilin-1, the catalytic core of γ-secretase. Therefore, we investigated the role of CASP4/11 in angiogenesis.Experimental Approach: In vivo, we studied the role of Casp11 in several angiogenesis mouse models using Casp11 wild-type and knockout mice. In vitro, we detected the effects of CASP4 on endothelial functions and Notch signalling by depleting or overexpressing CASP4 in human umbilical vein endothelial cells (HUVECs). The functional domain responsible for the binding of CASP4 and presenilin-1 was detected by mutagenesis and co-immunoprecipitation.Key Results: Casp11 deficiency impaired adult angiogenesis in ischaemic hindlimbs, melanoma xenografts and Matrigel plugs, but not the developmental angiogenesis of retina. Bone marrow transplantation revealed that the pro-angiogenic effect depended on CASP11 derived from non-haematopoietic cells. CASP4 expression was induced by inflammatory factors and CASP4 knockdown decreased cell viability, proliferation, migration and tube formation in HUVECs. Mechanistically, CASP4/11 deficiency increased Notch1 activation in vivo and in vitro, while CASP4 overexpression repressed Notch1 signalling in HUVECs. Moreover, CASP4 knockdown increased γ-secretase activity. The γ-Secretase inhibitor DAPT restored the effects of CASP4 siRNA on Notch1 activation and angiogenesis in HUVECs. Notably, the catalytic activity of CASP4/11 was dispensable. CASP4 directly interacted with presenilin-1 through the caspase recruitment domain (CARD).Conclusions and Implications: These findings reveal a critical role of CASP4/11 in adult angiogenesis and make this molecule a promising therapeutic target for angiogenesis-related diseases in the future. [ABSTRACT FROM AUTHOR]

Clinical trials of Dll4 (Delta-like 4) neutralizing antibodies (Dll4nAbs) in cancer patients are ongoing. Surprisingly, pulmonary hypertension (PH) occurs in 14% to 18% of patients treated with Dll4nAbs, but the mechanisms have not been studied. Here, PH progression was measured in mice treated with Dll4nAbs. We detected Notch signaling in lung tissues and analyzed pulmonary vascular permeability and inflammation. Notch target gene array was performed on adult human pulmonary microvascular endothelial cells (ECs) after inhibiting Notch cleavage. Similar mechanisms were studied in PH mouse models and pulmonary arterial hypertension patients. The rescue effects of constitutively activated Notch1 in vivo were also measured. We observed that Dll4nAbs induced PH in mice as indicated by significantly increased right ventricular systolic pressure, as well as pulmonary vascular and right ventricular remodeling. Mechanistically, Dll4nAbs inhibited Notch1 cleavage and subsequently impaired lung endothelial barrier function and increased immune cell infiltration in vessel walls. In vitro, Notch targeted genes' expression related to cell growth and inflammation was decreased in human pulmonary microvascular ECs after the Notch1 inactivation. In lungs of PH mouse models and pulmonary arterial hypertension patients, Notch1 cleavage was inhibited. Consistently, EC cell-cell junction was leaky, and immune cell infiltration increased in PH mouse models. Overexpression activated Notch1-attenuated progression of PH in mice. In conclusion, Dll4nAbs led to PH development in mice by impaired EC barrier function and increased immune cell infiltration through inhibition of Notch1 cleavage in lung ECs. Reduced Notch1 cleavage in lung ECs could be an underlying mechanism of PH pathogenesis. [ABSTRACT FROM AUTHOR]

Paeoniflorin has been demonstrated to exert anti-inflammatory and immunomodulatory effects in the animal study. In this study, we investigated immunoregulatory effects of paeoniflorin on anti-asthmatic effects and underlying mechanisms. Asthma model was established by ovalbumin-induced. A total of 50 mice were randomly assigned to five experimental groups: control, model, dexamethasone (2 mg/kg), and paeoniflorin (10 and 20 mg/kg). Airway resistance (Raw) were measured by the forced oscillation technique; histological studies were evaluated by the hematoxylin and eosin (HE) staining; Th1/Th2 cytokines were evaluated by enzyme-linked immunosorbent assay (ELISA); Th1/Th2 cells were evaluated by flow cytometry (FCM); and GATA3 and T-bet were evaluated by Western blot. Our study demonstrated that, compared with model group, paeoniflorin inhibited ovalbumin (OVA)-induced increases in Raw and eosinophil count; interleukin (IL)-4, IgE levels were recovered in bronchoalveolar lavage fluid compared; increased IFN-γ level in bronchoalveolar lavage fluid; histological studies demonstrated that paeoniflorin substantially inhibited OVA-induced eosinophilia in lung tissue and lung tissue compared with model group. Flow cytometry studies demonstrated that paeoniflorin can regulate Th1/Th2 balance. These findings suggest that paeoniflorin may effectively ameliorate the progression of asthma and could be used as a therapy for patients with allergic asthma. [ABSTRACT FROM AUTHOR]

Reactive nitrogen species are considered to participate in inflammation-related carcinogenesis through DNA damage. 8-Nitroguanine is a specific marker of inflammation-related carcinogenesis. Epstein-Barr virus infection-related nasopharyngeal carcinoma (NPC) is one of the most prevalent malignant tumors in southern China and Southeast Asia, and its prognosis has been poor for decades. Previously, we demonstrated that nitrative DNA damage, such as 8-nitroguanine formation, occurs in cancer cells of NPC patients (Ma et al. Int. J. Cancer 2008). In the present study, to investigate the involvement of stem cells in NPC, we performed immunohistochemical analyses to examine nitrative DNA lesions (8-nitroguanine) and several cancer stem / progenitor cell markers (CD44v6, CD24 and ALDH1A1) in nasopharyngeal tissues obtained from chronic nasopharyngitis and NPC patients. The staining intensity of 8-nitroguanine was significantly higher in cancer cells and inflammatory cells in stroma of NPC than in chronic nasopharyngitis tissues. Expression levels of CD44v6 and ALDH1A1 were significantly increased in cancer cells of primary NPC specimens in comparison to chronic nasopharyngitis tissues. 8-Nitroguanine was detected in CD44v6- or ALDH1A1-positive stem cells in NPC tissues. In the case of CD24 staining, there was no significant difference between NPC and chronic nasopharyngitis tissues. Intensive staining of CD44v6 and ALDH1A1 were also detected in NPC cell line HK1 compared to immortalized nasopharyngeal epithelial cells NP460 by a double immunofluorescence study and western blotting assay. In conclusion, CD44v6 and ALDH1A1 could be candidates of cancer stem cell markers for NPC. The present results indicate the possible mechanism by which inflammation causes NPC by inducing inflammatory processes and formation of 8-nitroguanine in CD44v6- and / or ALDH1A1-positive stem cells, and mutant stem cells participate in NPC development. [ABSTRACT FROM AUTHOR]

Platycodin D (PLD) is the major triterpene saponin in the root of Platycodon grandiflorum (Jacq.) with various pharmacological activities. The purpose of the present study was to evaluate the protective effects and possible mechanisms of PLD on acute lung injury (ALI) both in vivo and in vitro. In vivo, we used two ALI models, lipopolysaccharide (LPS)-induced ALI and bleomycin (BLE)-induced ALI to evaluate the protective effects and possible mechanisms of PLD. Female BALB/c mice were randomly divided into the following groups: control group, LPS group, LPS plus pre-treatment with dexamethasone (2 mg/kg) group, LPS plus pre-treatment with PLD groups (50 mg/kg, 100 mg/kg), LPS plus post-treatment with dexamethasone (2 mg/kg) group, LPS plus post-treatment with PLD groups (50 mg/kg, 100 mg/kg), BLE group, BLE plus pre-treatment with dexamethasone (2 mg/kg) group, BLE plus pre-treatment with PLD groups (50 mg/kg, 100 mg/kg), BLE plus post-treatment with dexamethasone (2 mg/kg) group, and BLE plus post-treatment with PLD groups (50 mg/kg, 100 mg/kg). PLD was orally administered before or after LPS or BLE challenge with mice. Mice were sacrificed, and lung tissues and bronchoalveolar fluid (BALF) were prepared for further analysis. Our results showed that PLD significantly decreased lung wet-to-dry weight ratio (lung W/D weight ratio), total leukocyte number and neutrophil percentage in the BALF, and myeloperoxidase (MPO) activity of lung in a dose-dependent manner. Besides, cytokine levels, including interleukin (IL)-6, tumor neurosis factor (TNF)-α were also found significantly inhibited in BALF. Furthermore, PLD effectively inhibited the expressions of nuclear factor κB (NF-κB), Caspase-3 and Bax in the lung tissues, as well as restored the expression of Bcl-2 in the lungs and improved the superoxide dismutase (SOD) activity in BALF. In vitro, we used LPS-challenged cell model to evaluate the protective effects and possible mechanisms of PLD. MLE-12 cells were stimulated with LPS in the presence and absence of PLD. The levels of TNF-α, IL-6 and the expressions of NF-κB, Caspase-3, and Bax were remarkably down-regulated, while the expression of bcl-2 was significantly up-regulated in PLD treatment groups in MLE-12 cells. These results showed that the administration of PLD improved ALI both in vivo and in vitro, possibly through suppressing apoptosis and inflammation. [ABSTRACT FROM AUTHOR]