Nuclear P53 Expression Research Articles

Regulation of p27 by ubiquitin ligases and its pathological significance in human lung carcinomas

Down-regulation of cyclin-dependent kinase inhibitor protein p27, due to enhanced degradation, is frequently observed in various cancers. The ubiquitin ligases that mediate this degradation have been identified as S-phase kinase-associated protein-2 (Skp2), Kip1 ubiquitylation-promoting complex (KPC), and p53-inducible protein with RING-H2 domain (Pirh2) as well. We investigated the correlation among expression of these 3 ligases and p27 status in surgical specimens of human lung carcinomas by immunohistochemical analysis. Among 93 cases, expressions of p27, Skp2, KPC, and Pirh2 were found in 89.2%, 59.1%, 59.1%, and 67.7%, respectively. Down-regulation of p27 in cancer cells was frequently observed in adenocarcinoma (AC) and squamous cell carcinoma (SCC), but not in small cell carcinoma (SmCC). Overexpression of ubiquitin ligases was variously observed among histological types: Skp2 was more frequently observed in SCC and SmCC, KPC in SCC and Pirh2 in AC, followed by SCC. Several novel findings were obtained: (i) cytoplasmic p27 was observed in 8.6%, most frequently in SCC (13.3%), and correlated with nodal metastasis (P=.0044), (ii) significant inverse correlation between nuclear p27 and Pirh2 expression was observed by statistical analysis and at the cellular level, and (iii) cytoplasmic Pirh2 and total (cytoplasmic and/or nuclear) Pirh2 were significantly correlated with the nodal status (P=.0225, 0.0314), the pathological stage (P=.0213, 0.0475) and recurrence-free survival (P=.0194, 0.0482, respectively) in AC. Altogether, our data suggests that p27 and its cognate ubiquitin ligases are specifically involved in the clinical profiles, and thus, molecular targeting of these ubiquitin ligases, in particular, Pirh2, may have therapeutic value for human lung carcinomas.

The protective effects of PCPA against monocrotaline-induced pulmonary arterial hypertension are mediated through the downregulation of NFAT-1 and NF-κB.

Inflammation and remodeling play a role in the pathogenesis of pulmonary arterial hypertension (PAH). Nuclear factor-κB (NF-κB) and nuclear factor of activated T cells-1 (NFAT-1) participate in inflammation and remodeling in a number of diseases. As a tryptophan hydroxylase inhibitor, 4-chloro-DL-phenylalanine (PCPA) had been reported to exert anti-inflammatory and remodeling effects. Therefore, we hypothesized that PCPA may attenuate monocrotaline (MCT)-induced PAH through the NFAT-1 and NF-κB signaling pathways. In order to confirm our hypothesis, we divided 68 Sprague-Dawley male rats into 4 groups as follows: the control, MCT, MCT + P1 and MCT + P2 groups. MCT was administered at a dose of 60 mg/kg once via intraperitoneal injection. PCPA was administered via intraperitoneal injection at a dose of 50 or 100 mg/kg once daily for 21 consecutive days. We then measured the hemodynamic index and morphological analysis was carried out on the lung tissues. Western blot analysis and immunohistochemistry were used to examine the levels of NFAT-1 and NF-κB p-65. The expression levels of phosphorylated inhibitor of NF-κB kinase (p-IKK), IKK, phosphorylated extracellular signal-regulated kinase (p-ERK), ERK, intercellular adhesion molecule-1 (ICAM-1) and interleukin-6 (IL-6) were examined by western blot analysis. MCT was found to significantly induce PAH, with inflammation and remodeling of the lung tissues. This was associatd with an increased expression of NFAT-1, p-IKK, p-ERK and nuclear p65. PCPA significantly attenuated MCT-induced inflammation and arterial remodeling, and decreased the expression of NFAT-1, as well as that of relevant proteins of the NF-κB signaling pathway. The above-mentioned findings suggest that the inhibitory effects of PCPA on MCT-induced inflammation and arterial remodeling are related to the downregulation of the NFAT-1 and NF-κB signaling pathways in rats with PAH.

Dietary luteolin attenuates chronic liver injury induced by mercuric chloride via the Nrf2/NF-κB/P53 signaling pathway in rats.

Mercury exposure is a common cause of metal poisoning which is biotransformed to highly toxic metabolites thus eliciting biochemical alterations and oxidative stress. Luteolin, a phenolic compound found in many natural products, has multiple biological functions. Our study was aimed to explore the biological effects of luteolin in a liver injury model induced in rats by mercuric chloride (HgCl2). Criteria for injury included liver enzyme, glutathione and malondialdehyde levels, histopathology, TUNEL assay, hepatocyte viability and reactive oxygen species levels. The results showed that luteolin protected against HgCl2-induced liver injury. Luteolin increased total nuclear factor-erythroid-2-related factor 2 (Nrf2) levels in the presence of HgCl2. Upregulation of its downstream factors, heme oxygenase-1 and NAD(P)H quinone oxidoreductase 1, was also observed. This suggested that protection by luteolin against HgCl2-induced liver injury involved Nrf2 pathway activation. Luteolin also decreased expression of nuclear factor-κB (NF-κB) and P53. HgCl2 exposure led to increased Bcl-associated X protein (Bax), and decreased Bcl-2-related protein long form of Bcl-x (Bcl-xL) and B-cell leukemia/lymphoma-2 (Bcl-2) expression, leading to an increased Bax/Bcl-2 ratio. Taken together, our data suggested that decreasing oxidative stress is a protective mechanism of luteolin against development of HgCl2-induced liver injury, through the Nrf2/NF-κB/P53 signaling pathway in rats.

Fluvastatin Prevents Lung Adenocarcinoma Bone Metastasis by Triggering Autophagy

Bone is one of the most preferred sites of metastasis in lung cancer. Currently, bisphosphonates and denosumab are major agents for controlling tumor-associated skeletal-related events (SREs). However, both bisphosphonates and denosumab significantly increase the risk for jaw osteonecrosis. Statins, 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors and the most frequently prescribed cholesterol-lowering agents, have been reported to inhibit tumor progression and induce autophagy in cancer cells. However, the effects of statin and role of autophagy by statin on bone metastasis are unknown. In this study, we report that fluvastatin effectively prevented lung adenocarcinoma bone metastasis in a nude mouse model. We further reveal that fluvastatin-induced anti-bone metastatic property was largely dependent on its ability to induce autophagy in lung adenocarcinoma cells. Atg5 or Atg7 deletion, or 3-methyadenine (3-MA) or Bafilomycin A1 (Baf A1) treatment prevented the fluvastatin-induced suppression of bone metastasis. Furthermore, we reveal that fluvastatin stimulation increased the nuclear p53 expression, and fluvastatin-induced autophagy and anti-bone metastatic activity were mostly dependent on p53.

Silibinin treatment prevents endotoxin-induced uveitis in rats in vivo and in vitro.

Uveitis, an intraocular inflammatory disease, occurs mostly in young people and can result in the loss of socioeconomic capabilities. Silibinin has been shown to exert anti-inflammatory effects in human retinal pigment epithelial (RPE) cells. The present study investigated the anti-inflammatory effect of silibinin pretreatment on endotoxin-induced uveitis (EIU) in rats and the mechanisms by which it exerts these effects. Uveitis was induced via injection of lipopolysaccharides (LPS) into Lewis rats. Twenty-four hours after the LPS injection, histological examination showed that silibinin decreased inflammatory cell infiltration in the anterior segment of the eyes of LPS-treated rats. Analyses of the aqueous humor showed that silibinin decreased cell infiltration, protein concentration, nitric oxide (NO), and prostaglandin (PG)-E2 production. Western blot analysis indicated that silibinin decreased the expression of inducible NO synthase (iNOS), cyclooxygenase (COX-2), and phosphorylated IkB in the iris-ciliary body (ICB). Immunohistochemistry showed that silibinin decreased intercellular adhesion molecule (ICAM-1) expression in the ICB. In addition, western blot analysis showed that silibinin attenuated the expression of iNOS, COX-2, ICAM-1, and nuclear p65 in LPS-treated RAW cells. In conclusion, silibinin pretreatment prevents EIU and the subsequent production of proinflammatory mediators and ICAM-1, at least in part, by blocking the NF-κB–dependent signaling pathway both in vivo and in vitro. These effects may contribute to the silibinin-mediated preventive effects on intraocular inflammatory diseases such as acute uveitis.

Cellular Senescence in Mouse Hippocampus After Irradiation and the Role of p53 and p21.

Diverse stress signals including irradiation may trigger cellular senescence. We asked whether irradiation induced senescence in mouse hippocampus, and whether p53 or p21 played a role in this response. Following whole-brain irradiation, polymerase chain reaction (PCR) arrays for senescence-associated genes showed increased expression of CDKN1A (p21) and CDKN2A (p19ARF) in mouse hippocampus at 9 weeks. Upregulation of p21 and p19ARF was confirmed using real-time PCR, which also demonstrated increased CDKN2A/p16INKa expression after irradiation. No altered regulation of another 17 senescence-associated genes was observed after irradiation. Immunohistochemistry revealed increased nuclear expression of p16INK4A, p19ARF, p53, p21, phosphorylated p38 (pp38), 4-hydroxy-2-nonenal, and interleukin-6 (IL6) in granule cells of dentate gyrus after irradiation. Increased p16 nuclear immunoreactivity was further observed in type -1 cells, the putative neural stem cells. γ-phosphorylated-histone-2A nuclear foci were also seen in dentate gyrus 9 weeks postirradiation. In nonirradiated mice knockout of the TRP53 or p21 gene, there was increased p16INK4A, p19ARF, and IL6, but not pp38 in dentate gyrus. We conclude that irradiation induces transcript and protein expression profile alterations in mouse dentate gyrus consistent with the senescence phenotype. Absence of p53 or p21 results in increase in baseline expression of senescence markers with no further increase in expression after irradiation.

Clinical significance of p53 protein, beta-catenin, and HER2 in patients with Epstein-Barr virus-associated gastric cancer.

22 Background: Epstein-Barr virus (EBV) infection can cause cancer tumorigenesis and malignant transformation of host cells through the activation of oncogenic pathways. Therefore, we assessed the expression of p53 protein, beta-catenin, and HER2 and their prognostic implication in patients with EBV-associated gastric cancer (EBVaGC). Methods: After reviewing 1318 consecutive cases of surgically resected or endoscopic submucosal dissected gastric cancers, 117 patients were identified as EBV-positive using EBV-encoded RNA in-situ hybridization. The results of immunohistochemistry were interpreted as follows: strong p53 nuclear expression in at least 50% of tumor nuclei was interpreted as a positive result; strong positive cytoplasmic-nuclear expression patterns for β-catenin ( ≥ 10%) were considered altered expression; moderate or strong complete or basolateral membrane staining in 10% of tumor cells for HER2 was reported as a positive results. Results: The median age of the patients was 62 years (32-80) and 93 (79.5%) were male. The pathologic stages were as follows : stage I (n = 74), stage II (n = 25), and stage III (n = 18). Among the 117 patients, immunohistochemical staining for p53 was performed in 105 patients and 25 patients (23.8%) were positive. Beta-catenin was positive in 10 patients (17.5%) and HER2 was positive in 8 patients (6.8%), respectively. The positive expression of p53 was significantly associated with a high T stage (p = 0.006). Conversely, more patients without lymph node metastasis were p53 positive (p = 0.013). In the univariate analysis, the patients with p53 positive tumors showed a significantly improved disease-free survival (DFS) compared to the patient with negative tumors (p = 0.022), although the p53 status was marginally associated with overall survival (OS)(p = 0.080). However, p53 expression showed no prognostic significance on DFS in the multivariate analysis. Meanwhile, beta-catenin and HER2 was not found to be associated with DFS and OS in the survival analysis. Conclusions: The current study found a significant correlation between p53 expression and tumor progression in patients with EBVaGC.

Stathmin 1 promotes the proliferation and malignant transformation of pancreatic intraductal papillary mucinous neoplasms.

Pancreatic intraductal papillary mucinous neoplasms (IPMNs) are a type of pancreatic tumor, which have been identified following improvements in diagnostic imaging. However, the malignant transformation of IPMN has been difficult to diagnose clinically. To date, the mechanisms driving the progression of IPMN to cancer remain to be fully elucidated. The present study focused on Stathmin 1 (STMN1), a protein that is associated with the development of various types of cancer. The expression of STMN1 was examined immunohistochemically in tissues from cases of IPMN. The correlation between the STMN1 staining and clinical pathological factors was evaluated, and the expression of STMN1, p27 and S-phase kinase-associated protein 2 (SKP2) were compared. High expression levels of STMN1 were significantly correlated with regions of malignancy, and was associated with high expression of SKP2, low expression of nuclear p27 and a high Ki-67 index. High expression levels of STMN1 and SKP2 were significantly correlated with the transformation of IPMN to carcinoma. In addition, within the regions of carcinoma, the expression of STMN1 was weak in regions of adenoma and high in the cancerous regions. It was concluded that the high expression of STMN1 contributed to tumor proliferation and malignant transformation in the patients with IPMN. These results suggested that characterization of the expression of STMN1 may be a promising approach for predicting malignant transformation of pancreatic intraductal papillary mucinous adenoma.

Clinical Significance of p53 Protein Expression, Beta-catenin Expression and HER2 Expression for Epstein-Barr Virus-associated Gastric Cancer.

This study assessed the expression of the p53 protein, beta-catenin, and HER2 and their prognostic implications in patients with EBV-associated gastric cancer (EBVaGC). After reviewing 1318 consecutive cases of surgically resected or endoscopic submucosal dissected gastric cancers, 117 patients were identified as EBV-positive using EBV-encoded RNA in-situ hybridization. The immunohistochemistry results were interpreted as follows: strong p53 nuclear expression in at least 50% of tumor nuclei was interpreted as a positive result, strong beta-catenin expression in at least 10% of cytoplasmic nuclei was interpreted as a positive result, and moderate or strong complete or basolateral membrane staining in 10% of tumor cells was interpreted as a positive result for HER2. Immunohistochemical staining for p53 was performed on tumor tissue from 105 patients, among whom 25 (23.8%) tested positive. Meanwhile, beta-catenin expression was positive in 10 patients (17.5%) and HER2 expression was positive in 8 patients (6.8%). The positive expression of p53 was significantly associated with a high T stage (p=0.006). More patients with lymph node metastasis were p53-positive (p=0.013). In the univariate analysis, the p53-positive patients showed significantly decreased disease-free survival (DFS) when compared with the p53-negative patients (p=0.022), although the p53 status was only marginally associated with overall survival (OS) (p=0.080). However, p53 expression showed no prognostic significance on DFS in the multivariate analysis. Moreover, beta-catenin and HER2 showed no association with DFS and OS in the survival analysis. The current study found a significant correlation between p53 expression and tumor progression and lymph node metastases in patients with EBVaGC.

Differential and correlated expressions of p16/p21/p27/p38 in mammary gland tumors of aged dogs.

The inhibitory effect of neutering on mammary gland tumor development in dogs has been well described. However, we observed that the effect of neutering on tumor malignancy may be altered by aging. Therefore, we characterized mammary tumors in aged dogs by analyzing the expression of cellular senescence markers. Expressions of p16, p38, p21, and p27 antibodies, which are senescence-associated markers, were assessed in canine mammary tumors of aged dogs via immunohistochemical analysis. In addition, correlations between those expressions were analyzed. Expression of p16 was negatively associated with strong nuclear p27 expression. Expression of p38 was observed in most of the mammary tumors examined, and negative p38 expression was related to positive p21 expression. Moreover, p21 expression was associated with p27 expression; negative p21 expression was associated with negative p27 expression, while positive p21 expression was associated with positive p27 expression. The results confirm that the p21- and p27-encoding genes have similar expression patterns in the mammary tumors of aged dogs. In the present study, we characterized the expression of cellular senescence markers in these tumors and elucidated the relationships among their expression patterns.

Saponin fraction isolated from Conyza blinii H.Lév. demonstrates strong anti-cancer activity that is due to its NF-κB inhibition

CBS (Conyza blinii saponin) is the total triterpenoidal saponins of Conyza blinii H.Lév which is a type of traditional Chinese medicine (TCM). We have discovered that CBS has a profound cytostatic activity against a range of solid tumour cells in a time- and dose-dependent manner. We also confirm that the cytostatic activity of CBS originates from its apoptosis induction effect. Additionally, we use immunoblot to find out that the apoptosis induction effect of CBS is attributable to the activation of mitochondrial pathway. Mechanistic study demonstrates that CBS is an effective NF-κB inhibitor. It inhibits p65 nuclear translocation and NF-κB downstream gene expression, including XIAP, survivin, Bcl-xL, COX-2, cyclin D1, MMP-2, MMP-9 in HeLa cells. Tumour xenografted animal models verify the anti-cancer efficacy in vivo. Tumour growth is significantly repressed in two CBS-treated groups compared with the controls (P < 0.001). CBS treatment (i.g.) leads to a 48.5% and 57.0% reduction in terms of tumour weight for the 10 and 20 mg/kg dosed groups respectively. Also no apparent observable adverse effects can be seen. These results suggest that CBS obliterate tumour, at least in part due to its NF-κB inhibition, which creates potential for CBS to be developed as a practical cancer treatment.

Expression of CD10 in cancer-associated fibroblasts and its effect on initiation and progression of colorectal carcinoma

Objective: To study CD10 expression in cancer-associated fibroblasts (CAF) and related effect on colorectal cancer initiation and progression. Methods: A total of 226 surgical removed colorectal cancer specimens were collected with patient follow-up data. A panel of immunohistochemical markers(CD10, Ki-67, p53, cyclin D1 and β-catenin) were evaluated in carcinomas, adjacent adenomas and paired normal colorectal mucosa with correlation of clinicopathological parameters. Results: CD10 expression was not detected in the normal colorectal mucosa by immunohistochemistry. The percentages of CD10 expression in CAF were 80.1% (181/226) in carcinoma tissue and 58.4% (132/226) in adjacent adenomas, respectively. SMA was positive and desmin was negative. The proliferation index of Ki-67 was 84.1%(190/226) in tumor tissue, 63.7%(144/226)in adenoma zone, and 7.1% (16/226) in the normal mucosa. The rate of p53 mutation was 50.4% (114/226)in tumor tissue, 53.1%(120/226)in adenoma and 8.8%(20/226)in the normal mucosa. The expression rate of cyclin D1 was 83.6%(189/226) in tumor tissue, 48.7%(110/226)in adenoma zone, but negative in the normal mucosa. For normal tissue, the percentages of β-catenin expression was 53.1%(120/226), 95.6%(216/226) and 10.6%(24/226) in the cell membrane, cytoplasm and nucleus, respectively.The β-catenin expression in cell membrane, cytoplasm and nucleus was 17.7%(40/226), 100.0% (226/226) and 49.1% (111/226), respectively, in the tumor cells. The expression of Ki-67, p53, cyclin D1 and β-catenin in the tumor cells was positively associated with CD10 in CAF (P<0.05). The CD10 expression was different in patients with different gender, age and differentiation degree (P<0.05), whereas the depth of invasion, lymph node metastasis and tumor emboli did not relate to it. Overall survival rates in CD10 negative group were higher than that in CD10 positive group. Conclusions: CD10 is only expressed in CAF. Significant correlation is found between CAF with high CD10 expression and neighboring tumor cells with p53, Ki-67 and cyclin D1 expression and nuclear β-catenin expression. CD10-positive CAF and p53, β-catenin, cyclin D1 and Ki-67-labelled colorectal cancer cells together with nuclear β-catenin expression may provide helps for diagnosis of colorectal carcinoma from an angle of tumor interstitial microenvironment. CAF with CD10 expression may promote the initiation and progression of colon cancer cells by activating Wnt signaling pathway.

Cyclins A, B, E and p27 in Endometrial Endometrioid Adenocarcinoma

We have previously shown that cyclin A, B and E hold prognostic significance in endometrial endometrioid adenocarcinoma. The aim of this study was to investigate the impact of cyclin-dependent kinase inhibitor p27 on cancer-specific survival and other clinicopathological variables, as well as further analyze the relationship between p27 and cyclins A, B and E and their combined relation to prognosis in the disease. The study comprised of 211 patients surgically treated for endometrial endometrioid adenocarcinoma at the Oulu University Hospital between 1992 and 2000. Tissue samples were immunohistochemically stained for cyclins A, B and E, as well as p27. Clinicopathological data were retrospectively retrieved from the patients' records. In this study, universally low cyclin expression was found to be an independent, favorable prognostic factor in endometrial endometrioid adenocarcinoma. A strong correlation was found between cyclin A and cyclin B expression and weaker correlations between other cyclin and p27 pairs. Nuclear p27 expression correlated with stage and produced near-significant results in univariate survival analysis. Combining the expression level of different cyclins may be useful in determining the prognosis in endometrial cancer. Unfortunately, it remains unclear whether high p27 expression is a poor or a favorable prognostic factor. Further large-scale studies are required to assess the effects of cyclins and p27 in endometrial cancer.

Expression of protein p27 in various forms of seborrheic keratosis

The significant role in the pathogenesis of seborrheic keratosis (SK) plays the violation of the cell cycle regulation. According to the research unit the cell proliferation in acanthotic and irritated histological types of SK is regulated by p27 (Kip1), cyclin-dependent kinase inhibitor. Considering the variety of histological types of SK, definition of p27 expression will reveal the characteristic features of the cell cycle disorders and proliferation for each type of tumor. Material and Methods. Of the 102 tumors from patients with SK, according to the results of histological examination, were selected 10 specimens of each histological types of SK: acanthotic, hyperkeratotic, adenoid, irritated, and clonal. We assessed all specimens for p27 (Kip1) expression using immunohistochemistry (monoclonal antibody p27 at a dilution of 1:20 (Novocastra Laboratories Ltd.). Three skin biopsy samples of healthy individuals were included. Results. Severe diffuse nuclear expression of p27 was present in all cases of adenoid, irritated, and 4 cases of clonal histological types of SK. In other tumor types positive reaction with monoclonal antibody to p27 was reduced as compared with healthy skin were recorded single positively stained nuclei of basal cells. Conclusions. Thus, we have found a violation of p27 protein expression in all types of seborrheic keratosis as with the excess (adenoid, irritated, clonal SK type) and in p27 protein deficiency (acanthotic, hyperkeratotic) normal course of cell cycle phases is broken. This leads to the disappearance of control over the cell proliferative activity and apoptosis, facilitating a slow, uncontrolled growth of SK cells.

Recurrence of giant cell tumour of bone: role of p53, cyclin D1, β-catenin and Ki67.

To determine various clinical, radiographic, and pathological parameters which may indicate an increased risk of Giant cell tumour of bone (GCTB) recurrence after surgical therapy. The study included a total of 164 GCTB samples; 118 (72%) primary tumours, and 46 (28%) recurrences; which were analyzed on immunohistochemistry for expression of Ki67, p53, cyclin D1, and β-catenin. Among 13 analyzed clinical, radiological, and histological variables, which presented possible predictive factors for the incidence of GCTB relapse, univariate logistic regression (ULR) extract three highly statistically significant parameters: 1) lesion localization, 2) nuclear p53 expression in mononuclear cells, and 3) nuclear cyclin D1 expression in giant multinuclear cells. The multivariate logistic regression (MLR), revealing that p53 expression in mononuclear cells was the most significant predictive factor (HR = 6,181 p < 0,001), the positivity of which indicated six times higher probability for recurrence in GCTB. The expression of cyclin D1 in giant cells, containing less than 15 nuclei, was also statistically significant (HR = 8,398, p = 0,038) for predicting the recurrence, and demonstrated eight times more frequent recurrence in positive tumours. This study confirmed independent predicting factors for GCTB reccurence: p53 expression in mononuclear tumour cells and cyclin D1 expression in giant multinuclear cells. Results are new addition to generally known parameters, such as: localization of lesion, number of surgical interventions, clear destruction of cortex with the presence of extracompartmental lesion, and histological criteria for malignancy and can help in further research and treatment of GCTB.

Guhong injection protects against focal cerebral ischemia-reperfusion injury via anti-inflammatory effects in rats.

Guhong injection (GHI), composed of aceglutamide and safflower aqueous extract, has been used clinically for the treatment of cerebrovascular diseases such as cerebral embolism, hemorrhage and mental deterioration. In this paper, we reported the results of the first study on the anti-inflammatory effects of GHI in murine focal cerebral ischemia-reperfusion (I/R) injury. Adult male SD rats were randomly divided into six groups: Sham group, I/R group, GHI-L group (2.5mL/kg), GHI-M group (5mL/kg), GHI-H group (10mL/kg) and Nimodipine group. I/R injury was induced by middle cerebral artery occlusion (MCAO) for 1.5h followed by reperfusion for 24h. Compared with I/R group, rats treated with GHI showed dose dependent reductions in neurological defect scores and cerebral infarct volume. GHI obviously down-regulated nitric oxide (NO), inducible NO synthase (iNOS), myeloperoxidase (MPO), interleukin-1β (IL-1β), TNF-α (tumor necrosis factor-α) and C reactive protein (CRP) levels in serum. Moreover, histological examination by H&E staining showed that clear cell outline, less vacuolated spaces and largely surviving neurons were observed in GHI-treated rats. The immunohistochemical staining revealed that GHI administration significantly diminished the positive expressions of intercellular cell adhesion molecule-1 (ICAM-1) and nuclear factor-κB p65 (NF-κB p65) in brain tissues. Western blot analysis for ICAM, NF-κB p65 and iNOS furthersolidified the above findings. All these results demonstrate that GHI exerts a strong and ameliorative effect on cerebral I/R injury in rats possibly through the inhibition of inflammation.

Vitamin D3 Partly Antagonizes Advanced-Glycation Endproducts-Induced NFκB Activation in Mouse Podocytes

Background/Aims: We have previously shown that advanced glycation-endproducts (AGEs) induced NFκB activation in differentiated mouse podocytes. This NFκB activation may contribute to the progression of renal disease and mediation of fibrosis by various mechanisms. This study was undertaken to test whether this detrimental response may be reversed by vitamin D3 or its analogue paricalcitol. Methods: Differentiated mouse podocytes were challenged with glycated bovine serum albumin (AGE-BSA), or non-glycated control BSA (in the presence or absence of various concentrations of vitamin D3 (decostriol, 1α,25-dihydroxyvitamin D3)) or its active analog paricalcitol. Quantitative mRNA expressions were measured by real-time PCR, whereas protein expressions were determined by Western blotting followed by densitometry. Cytoplasmic and nuclear protein expression of the NFκB subunit p65 (Rel A) were determined by Western blotting. Furthermore, the ratio of phosphorylated to non-phosphorylated IκB-α was measured using specific antibodies. Electrophoretic mobility shift assays and a capture ELISA assay were used to assess NFκB transactivation in vitro. In addition, NFκB transactivation was also monitored in HEK-NFκBIA reporter cells using live cell luminometry. Results: Podocytes expressed the receptor for vitamin D. The vitamins did not suppress receptor for AGEs (RAGE) expression; instead, they rather upregulated RAGE. Although vitamin D3 and paricalcitol partly and differentially modified some of the studied parameters, both hormones inhibited AGE-BSA-induced NFκB transactivation, presumably by various mechanisms including the upregulation of IκB-α protein, keeping NFκB sequestered in an inactive state in the cytoplasm. Conclusion: Vitamin D3 or its analog paricalcitol partly prevented AGE-mediated NFκB activation, an important feature of diabetic nephropathy (DN). Whether this in vitro finding is of clinical relevance to prevent/treat DN requires further studies.

Suppression of human 8-oxoguanine DNA glycosylase (OGG1) augments ultrasound-induced apoptosis in cervical cancer cells

PurposeHuman 8-oxoguanine DNA glycosylase (OGG1) is a major base excision repair enzyme, and it was reported to suppress the activation of intrinsic apoptotic signaling pathway in response to oxidative stress. In this study, our aim was to investigate the effects of OGG1 downregulation on ultrasound-induced apoptosis in cervical cancer cells. MethodsOGG1 expression was silenced by shRNA in the cervical cancer SW756 and CaSki cells. Cell viability was evaluated by MTT assay after OGG1 knockdown following ultrasound treatment. Ultrasound-induced apoptosis was measured by Annexin V-FITC/propidium iodide. Intracellular reactive oxygen species (ROS) production and Ca2+ concentration were detected using a fluorescent probe, 2′,7′-dichlorofluorescin diacetate (DCFH-DA) and a green fluorescent dye fluo-4AM, respectively. Western blotting was used to analyze the expression of Bcl-2, Bax, cleaved caspase-3, and nuclear factor-κB p65 (NF-κB p65). ResultsThe results indicated that OGG1 knockdown did not suppress cell proliferation, but significantly augmented ultrasound-induced inhibitory effects on the cell viability, and increased ultrasound-induced early apoptosis and late apoptosis and necrosis in the SW756 and CaSki cells when exposure to ultrasound (1MHz) at 1.5W/cm2 for 30 and 60s. OGG1 knockdown significantly increased intracellular ROS production and Ca2+ concentration after incubation of 6, 24, and 48h post-ultrasound treatment. The downregulation of Bcl-2 protein and the upregulation of Bax, cleaved caspase-3, and NF-κB p65 protein levels were observed in the shRNA-OGG1 cells and mock-shRNA cells, but no significant change of these protein levels was found between of them. ConclusionsThese results indicate that downregulation of OGG1 expression can augment ultrasound-induced apoptosis in cervical cancer cells, which suggests that OGG1 suppression might provide a new insight for ultrasound-induced therapeutic effects on cervical cancer treatment.

Carvacrol Exerts Neuroprotective Effects Via Suppression of the Inflammatory Response in Middle Cerebral Artery Occlusion Rats.

Increasing evidence demonstrates that inflammation plays an important role in cerebral ischemia. Carvacrol, a monoterpenic phenol, is naturally occurring in various plants belonging to the family Lamiaceae and exerts protective effects in a mice model of focal cerebral ischemia/reperfusion injury by reducing infarct volume and decreasing the expression of cleaved caspase-3. However, the anti-inflammatory mechanisms by which carvacrol protect the brain have yet to be fully elucidated. We investigated the effects of carvacrol on inflammatory reaction and inflammatory mediators in middle cerebral artery occlusion rats. The results of the present study showed that carvacrol inhibited the levels of inflammatory cytokines and myeloperoxidase (MPO) activity, as well as the expression of iNOS and COX-2. It also increased SOD activity and decreased MDA level in ischemic cortical tissues. In addition, carvacrol treatment suppressed the ischemia/reperfusion-induced increase in the protein expression of nuclear NF-kB p65. In conclusion, we have shown that carvacrol inhibits the inflammatory response via inhibition of the NF-kB signaling pathway in a rat model of focal cerebral ischemia. Therefore, carvacrol may be a potential therapeutic agent for the treatment of cerebral ischemia injury.

Fluorofenidone attenuates pulmonary inflammation and fibrosis via inhibiting the activation of NALP3 inflammasome and IL-1β/IL-1R1/MyD88/NF-κB pathway.

Interleukin (IL)‐1β plays an important role in the pathogenesis of idiopathic pulmonary fibrosis. The production of IL‐1β is dependent upon caspase‐1‐containing multiprotein complexes called inflammasomes and IL‐1R1/MyD88/NF‐κB pathway. In this study, we explored whether a potential anti‐fibrotic agent fluorofenidone (FD) exerts its anti‐inflammatory and anti‐fibrotic effects through suppressing activation of NACHT, LRR and PYD domains‐containing protein 3 (NALP3) inflammasome and the IL‐1β/IL‐1R1/MyD88/NF‐κB pathway in vivo and in vitro. Male C57BL/6J mice were intratracheally injected with Bleomycin (BLM) or saline. Fluorofenidone was administered throughout the course of the experiment. Lung tissue sections were stained with haemotoxylin and eosin and Masson's trichrome. Cytokines were measured by ELISA, and α‐smooth muscle actin (α‐SMA), fibronectin, collagen I, caspase‐1, IL‐1R1, MyD88 were measured by Western blot and/or RT‐PCR. The human actue monocytic leukaemia cell line (THP‐1) were incubated with monosodium urate (MSU), with or without FD pre‐treatment. The expression of caspase‐1, IL‐1β, NALP3, apoptosis‐associated speck‐like protein containing (ASC) and pro‐caspase‐1 were measured by Western blot, the reactive oxygen species (ROS) generation was detected using the Flow Cytometry, and the interaction of NALP3 inflammasome‐associated molecules were measured by Co‐immunoprecipitation. RLE‐6TN (rat lung epithelial‐T‐antigen negative) cells were incubated with IL‐1β, with or without FD pre‐treatment. The expression of nuclear protein p65 was measured by Western blot. Results showed that FD markedly reduced the expressions of IL‐1β, IL‐6, monocyte chemotactic protein‐1 (MCP‐1), myeloperoxidase (MPO), α‐SMA, fibronectin, collagen I, caspase‐1, IL‐1R1 and MyD88 in mice lung tissues. And FD inhibited MSU‐induced the accumulation of ROS, blocked the interaction of NALP3 inflammasome‐associated molecules, decreased the level of caspase‐1 and IL‐1β in THP‐1 cells. Besides, FD inhibited IL‐1β‐induced the expression of nuclear protein p65. This study demonstrated that FD, attenuates BLM‐induced pulmonary inflammation and fibrosis in mice via inhibiting the activation of NALP3 inflammasome and the IL‐1β/IL‐1R1/MyD88/ NF‐κB pathway.