Arsenic Accumulation and Physiological Response of Three Leafy Vegetable Varieties to As Stress.

Arsenic (As) in leafy vegetables may harm humans. Herein, we assessed As accumulation in leafy vegetables and the associated physiological resistance mechanisms using soil pot and hydroponic experiments. Garland chrysanthemum (Chrysanthemum coronarium L.), spinach (Spinacia oleracea L.), and lettuce (Lactuca sativa L.) were tested, and the soil As safety threshold values of the tested leafy vegetables were 91.7, 76.2, and 80.7 mg kg−1, respectively, i.e., higher than the soil environmental quality standard of China. According to growth indicators and oxidative stress markers (malondialdehyde, the ratio of reduced glutathione to oxidized glutathione, and soluble protein), the order of As tolerance was: GC > SP > LE. The high tolerance of GC was due to the low transport factor of As from the roots to the shoots; the high activity of superoxide dismutase, glutathione peroxidase, and catalase; and the high content of phytochelatin in the roots. Results of this work shed light on the use of As-contaminated soils and plant tolerance of As stress.

Transarterial chemoembolization versus percutaneous microwave coagulation therapy for recurrent unresectable intrahepatic cholangiocarcinoma: Development of a prognostic nomogram.

BACKGROUND: Transarterial chemoembolization (TACE) and percutaneous microwave coagulation therapy (PMCT) are commonly used to treat intrahepatic recurrent liver cancers. However, there is no information regarding their effectiveness in patients with recurrent intrahepatic cholangiocarcinoma (ICC) after resection. METHODS: A total of 275 patients with localized recurrent ICC who received either TACE (n = 183) or PMCT (n = 92) were studied. A propensity score matching analysis was performed to compare prognostic impact of TACE and PMCT. Prognostic factors for TACE and PMCT were identified respectively. Predictive nomograms for each TACE and PMCT were developed using the Cox independent prognostic factors and were validated in independent patient groups by receiver operating characteristic curves and area under curve values. RESULTS: Both TACE and PMCT provided curativeness in partial patients (5-year overall survival: 21.4% and 6.1%, respectively), but TACE provided better survival benefit in both overall patients (hazard ratio [HR] = 0.71; 95% confidence interval [CI]: 0.50-0.97; P = 0.034) and propensity score matching analysis (HR = 0.69; 95% CI: 0.47-0.98; P = 0.041). Independent prognostic factors for TACE were tumor size >5 cm, poor differentiation, and major resection, whereas poor differentiation, hepatitis B virus infection, cholelithiasis, and lymph node metastasis were identified for PMCT. Both predictive nomograms for TACE and PMCT were validated to be effective with area under curve values of 0.77 and 0.70, respectively. CONCLUSIONS: TACE provided better survival benefits compared to PMCT. However, there was a disparity in prognostic factors, suggesting evaluation of the two nomograms may be supportive in modality selection. Further prospective validation studies are required for the results to be applied in clinical medicine.

[Effects of copper content on the antibacterial performance and corrosion resistance of CoCrMoCu alloy].

OBJECTIVE: This study aimed to determine the effects of copper content on the corrosion resistance of CoCrMoCu alloy and its in vitro antibacterial performance. METHODS: CoCrMoCu specimens with different Cu contents (2%, 3%, 5%, and 7%) were prepared by vacuum melting method. CoCrMo without Cu served as control. The corrosion resistance of the specimens was measured by electrochemistry. The antibacterial effects of the specimens on Staphylococcus aureus and Escherichia coli were analyzed by coating-film method. RESULTS: Compared with CoCrMo without Cu, the addition of 2%-5% Cu to CoCrMo improved the pitting and uniform corrosion of CoCrMo alloy and decreased the corrosion current density. The antibacterial performance of CoCrMoCu alloy increased with increased Cu content. The antibacterial rate of alloy was 99% when Cu content exceeded 5%. CONCLUSIONS: Cu addition had a statistically significant influence on the corrosion resistance and antibacterial performance of CoCrMoCu. CoCrMoCu has better corrosion resistance and antibacterial performance when Cu content is 5%.

[Characteristics and Formation Mechanism of a Multi-Day Haze in the Winter of Shijiazhuang Using a Single Particle Aerosol Mass Spectrometer (SPAMS)].

A multi-day haze episode occurred in Shijiazhuang during November 18-26, 2014. The characteristics were studied based on the data collected by the single particle aerosol mass spectrometer (SPAMS) located in the automatic monitoring station (20 meters) of Shijiazhuang. In accordance with the source spectral library of atmospheric pollutant emissions in Shijiazhuang, the main sources were distinguished and analyzed. The mass concentration of particulate matters and meteorological conditions being taken in account, the causes of haze in winter were also studied. It turned out that fine particulate matters in the Shijiazhuang air were mainly from 7 different sources: the tracer ion of coal source was Al; the tracer ions of industry sources were OC, Fe, and Pb; the tracer ion of motor vehicle tail gas source was EC; the tracer ions of dust source were Al, Ca and Si; the tracer ions of biomass burning source were K and levoglucosan; the tracer ions of pure secondary inorganic source were SO4-, NO2-, and NO3-, and the tracer ion of dining source was HOC. Of the above mentioned, OC, HOC, EC, HEC, ECOC, rich potassium particles minerals and heavy metals were 8 dominant polluting groups in hazy days. OC and ECOC particles were the majority, which accounted for more than 50% and 20% of the overall measured particles. OC particles were mainly discharged from coal combustion and industrial processes, and ECOC particles were mainly from coal combustion and vehicle exhaust emissions. When haze occurred in Shijiazhuang the proportion of pollutant particles of NH4+, SO4- , NO2- and NO3- increased, of which NH4+ was the most sharply increased. The mixed degree between EC, OC and NH4+, So4-, NO3- in the haze was higher than usual, of which NH4+ was the most sharply increased. In the static and stable weather gaseous (SO2, NO(x), NH3, VOCs) pollutants and particles were difficult to spread and accumulated rapidly, which were discharged from coal combustion, the process of the medical industry and the automobile exhaust. The gaseous pollutants tended to react for the second time and formed the ammonium nitrate and ammonium sulfate particles. Secondary particles were formed by collision and mixed with each other adequately or mildly, which caused the reduction of atmospheric visibility. This was the main cause for the haze during the winter in Shijiazhuang.

High expression of proline-rich tyrosine kinase 2 is associated with poor survival of hepatocellular carcinoma via regulating phosphatidylinositol 3-kinase/AKT pathway.

BACKGROUND: The peritumoral environment has been implicated to be important in the process of metastasis and recurrence in hepatocellular carcinoma (HCC). Our aims were to assess the prognostic value of proline-rich tyrosine kinase 2 (Pyk2) in HCC and investigate related molecular mechanism. METHODS: Expression of Pyk2 was tested by immunohistochemistry in tissue microarrays containing 141 paired HCC samples. Correlation between Pyk2 and vascular endothelial growth factor (VEGF) expression in clinical samples was analyzed by Spearman rank correlation. Matrigel invasion, anchorage-independent growth assay and immunoblotting were performed to study the effect of Pyk2 on the invasion and progression of HCC cells and phosphoinositide 3-kinase (PI3K)/AKT pathway activation. RESULTS: Higher Pyk2 density in both tumor and peritumor was associated with lower overall survival (P = 0.044; P = 0.041, respectively), serum AFP levels > 1,000 ng/ml (P = 0.013; P = 0.032, respectively) and postoperative distant metastasis (both P < 0.001). However, only higher peritumoral Pyk2 density was related to lower disease-free survival (P = 0.014) and vascular invasion (P = 0.035). A significant correlation between Pyk2 and VEGF density in tumor or peritumoral liver tissue was observed (r = 0. 3133, P = 0.0002; r = 0.5176, P < 0.0001, respectively). Immunoblotting showed that Pyk2 activated PI3K-AKT pathway to upregulate VEGF expression in HL-7702, SMMC-7721 and HepG2 cells. CONCLUSIONS: High Pyk2, especially peritumoral Pyk2 was associated with poor survival, disease recurrence, and metastasis in HCC. PI3K-AKT pathway was involved in Pyk2-mediated VEGF expression during HCC progression and invasion.

p28(GANK) prevents degradation of Oct4 and promotes expansion of tumor-initiating cells in hepatocarcinogenesis.

BACKGROUND & AIMS: Hepatocellular carcinoma (HCC) is believed to arise from tumor-initiating cells (T-ICs), although little is known about their stem cell-like properties. METHODS: We quantified levels of p28(GANK) (Gankyrin), OV6, and Oct4 in 130 human HCC samples using immunohistochemistry. Magnetic-activated cell sorting was used to isolate OV6+ HCC cells. T-IC properties were evaluated by quantitative reverse-transcription polymerase chain reaction, flow cytometry, and spheroid formation. We used a coimmunoprecipitation assay to study interactions among p28(GANK), Oct4, and WWP2. Tumorigenicity and pulmonary metastasis were examined in nonobese diabetic and severe combined immunodeficient mice. RESULTS: In HCC samples, high levels of p28(GANK) correlated with expansion of OV6+ tumor cells; the combination of high levels of p28(GANK) and OV6 was associated with progression of HCC. p28(GANK) was predominantly expressed in liver T-ICs, isolated by magnetic sorting, and undifferentiated primary HCC spheroids. Increased levels of p28(GANK) in T-ICs increased their percentages in HCC samples, expression of stem cell genes, self-renewal potential, chemoresistance in vitro, and tumorigenicity and ability to develop into pulmonary metastases in mice. Conversely, knockdown of p28(GANK) reduced their T-IC properties. p28(GANK) likely activates liver T-ICs by impeding ubiquitination and degradation of the transcription factor Oct4 by WWP2. In support of this concept, levels of p28(GANK) correlated with those of Oct4 in HCC samples. CONCLUSIONS: p28(GANK) activates and maintains liver T-ICs in HCCs by preventing degradation of Oct4. Inhibitors of p28(GANK) might therefore be developed to inactivate T-ICs and slow tumor progression.

The oncoprotein p28GANK establishes a positive feedback loop in ß-catenin signaling.

p28(GANK) (also known as PSMD10 or gankyrin) is a novel oncoprotein that is highly expressed in hepatocellular carcinoma (HCC). Through its interaction with various proteins, p28(GANK) mediates the degradation of the tumor suppressor proteins Rb and p53. Although p53 was reported to downregulate ß-catenin, whether p28(GANK) is involved in the regulation of ß-catenin remains uncertain. Here we report that both growth factors and Ras upregulate p28(GANK) expression through the activation of the phosphoinositide 3-kinase-AKT pathway. Upregulation of p28(GANK) expression subsequently enhanced the transcription activity of ß-catenin. This effect was observed in p53-deficient cells, suggesting a p53-independent mechanism for the p28(GANK)-mediated activation of ß-catenin. p28(GANK) overexpression also reduced E-cadherin protein levels, leading to increased release of free ß-catenin into the cytoplasm from the cadherin-bound pool. Interestingly, exogenous expression of p28(GANK) resulted in elevated expression of the endogenous protein. We also observed that both ß-catenin and c-Myc were transcriptional activators of p28(GANK), and a correlation between p28(GANK) overexpression and c-Myc, cyclin D1 and ß-catenin activation in primary human HCC. Together, these results suggest that p28(GANK) expression is regulated by a positive feedback loop involving ß-catenin, which may play a critical role in tumorigenesis and the progression of HCC.

Zinc finger protein ZBTB20 expression is increased in hepatocellular carcinoma and associated with poor prognosis.

BACKGROUND: Our previous studies showed that ZBTB20, a new BTB/POZ-domain gene, could negatively regulate α feto-protein and other liver-specific genes, concerning such as bio-transformation, glucose metabolism and the regulation of the somatotropic hormonal axis. The aim of this study is to determine the potential clinical implications of ZBTB20 in hepatocellular carcinoma (HCC). METHODS: Quantitative real-time RT-PCR and Western blot analyses were used to detect expression levels of ZBTB20 in 50 paired HCC tumorous and nontumorous tissues and in 20 normal liver tissues. Moreover, expression of ZBTB20 was assessed by immunohistochemistry of paired tumor and peritumoral liver tissue from 102 patients who had undergone hepatectomy for histologically proven HCC. And its relationship with clinicopathological parameters and prognosis was investigated. RESULTS: Both messenger RNA and protein expression levels of ZBTB20 were elevated significantly in HCC tissues compared with the paired non-tumor tissues and normal liver tissues. Overexpressed ZBTB20 protein in HCC was significantly associated with vein invasion (P=0.016). Importantly, the recurrence or metastasis rates of HCCs with higher ZBTB20 expression were markedly greater than those of HCCs with lower expression (P=0.003, P=0.00015, respectively). Univariate and multivariate analyses revealed that ZBTB20 overexpression was an independent prognostic factor for HCC. The disease-free survival period and over-all survival period in patients with overexpressed ZBTB20 in HCC was significantly reduced. CONCLUSIONS: The expression of ZBTB20 is increased in HCC and associated with poor prognosis in patients with HCC, implicating ZBTB20 as a candidate prognostic marker in HCC.

p28GANK overexpression accelerates hepatocellular carcinoma invasiveness and metastasis via phosphoinositol 3-kinase/AKT/hypoxia-inducible factor-1α pathways.

UNLABELLED: The overall survival of patients with hepatocellular carcinoma (HCC) remains poor, and the molecular mechanisms underlying HCC progression and aggressiveness are unclear. Here, we report that increased expression of p28(GANK) (Gankyrin, PSMD10, or p28) in human HCC predicts poor survival and disease recurrence after surgery. Patients with HCC who have large tumors, with vascular invasion and intrahepatic or distant metastasis, expressed high levels of p28(GANK) . Invasive tumors overexpressing p28(GANK) were featured by active epithelial-mesenchymal transition (EMT), and exhibited increased angiogenesis associated with vascular endothelial growth factor overexpression, whereas silencing p28(GANK) expression attenuated EMT and motility/invasion of tumor cells. The p28(GANK) activates phosphoinositide 3-kinase (PI3K)-V-akt Murine Thymoma Viral Oncogene Homolog (AKT)-hypoxia-inducible factor 1α (HIF-1α) signaling to promote TWIST1, vascular endothelial growth factor, and metalloproteinase 2 expression. Suppression of the PI3K-AKT-HIF-1α pathway interfered with p28(GANK) -mediated EMT and invasion. Consistently, we detected a significant correlation between p28(GANK) expression and p-AKT levels in a cohort of HCC biopsies, and the combination of these two parameters is a more powerful predictor of poor prognosis. CONCLUSION: These results present novel mechanistic insight into a critical role of p28(GANK) in HCC progression and metastasis.

p28GANK inhibits endoplasmic reticulum stress-induced cell death via enhancement of the endoplasmic reticulum adaptive capacity.

It has been shown that oncoprotein p28(GANK), which is consistently overexpressed in human hepatocellular carcinoma (HCC), plays a critical role in tumorigenesis of HCC. However, the underlying mechanism remains unclear. Here, we demonstrated that p28(GANK) inhibits apoptosis in HCC cells induced by the endoplasmic reticulum (ER) stress. During ER stress, p28(GANK) enhances the unfolded protein response, promotes ER recovery from translational repression, and thereby facilitates cell's ability to cope with the stress conditions. Furthermore, p28(GANK) upregulates glucose-regulated protein 78 (GRP78), a key ER chaperone protein, which subsequently enhances the ER folding capacity and promotes recovery from ER stress. We also demonstrated that p28(GANK) increases p38 mitogen-activated protein kinase and Akt phosphorylation, and inhibits nuclear factor kappa B (NF-kappaB) activation under ER stress, which in turn contributes to GRP78 upregulation. Taken together, our results indicate that p28(GANK) inhibits ER stress-induced apoptosis in HCC cells, at least in part, by enhancing the adaptive response and GRP78 expression. We propose that p28(GANK) has potential implications for HCC progression under the ER stress conditions.

Oncoprotein p28 GANK binds to RelA and retains NF-kappaB in the cytoplasm through nuclear export.

p28(GANK) (also known as PSMD10, p28 and gankyrin) is an ankyrin repeat anti-apoptotic oncoprotein that is commonly overexpressed in hepatocellular carcinomas and increases the degradation of p53 and Rb. NF-kappaB (nuclear factor-kappaB) is known to be sequestered in the cytoplasm by I kappaB (inhibitor of NF-kappaB) proteins, but much less is known about the cytoplasmic retention of NF-kappaB by other cellular proteins. Here we show that p28(GANK) inhibits NF-kappaB activity. As a nuclear-cytoplasmic shuttling protein, p28(GANK) directly binds to NF-kappaB/RelA and exports RelA from nucleus through a chromosomal region maintenance-1 (CRM-1) dependent pathway, which results in the cytoplasmic retention of NF-kappaB/RelA. We demonstrate that all the ankyrin repeats of p28(GANK) are required for the interaction with RelA and that the N terminus of p28(GANK), which contains the nuclear export sequence (NES), is responsible for suppressing NF-kappaB/RelA nuclear translocation. These results suggest that overexpression of p28(GANK) prevents the nuclear localization and inhibits the activity of NF-kappaB/RelA.