Expression of DNA Damage Response Molecules PARP1, γH2AX,BRCA1, and BRCA2 Predicts Poor Survival of Breast Carcinoma Patients

BACKGROUND: Poly(ADP-ribose) polymerase 1 (PARP1), γH2AX, BRCA1, and BRCA2 are conventional molecular indicators of DNA damage in cells and are often overexpressed in various cancers. In this study, we aimed, using immunohistochemical detection, whether the co-expression of PARP1, γH2AX, BRCA1, and BRCA2 in breast carcinoma (BCA) tissue can provide more reliable prediction of survival of BCA patients. MATERIALS AND METHODS: We investigated immunohistochemical expression and prognostic significance of the expression of PARP1, γH2AX, BRCA1, and BRCA2 in 192 cases of BCAs. RESULTS: The expression of these four molecules predicted earlier distant metastatic relapse, shorter overall survival (OS), and relapse-free survival (RFS) by univariate analysis. Multivariate analysis revealed the expression of PARP1, γH2AX, and BRCA2 as independent poor prognostic indicators of OS and RFS. In addition, the combined expressional pattern of BRCA1, BRCA2, PARP1, and γH2AX (CSbbph) was an additional independent prognostic predictor for OS (P < .001) and RFS (P < .001). The 10-year OS rate was 95% in the CSbbph-low (CSbbph scores 0 and 1) subgroup, but that was only 35% in the CSbbph-high (CSbbph score 4) subgroup. CONCLUSION: This study has demonstrated that the individual and combined expression patterns of PARP1, γH2AX, BRCA1, and BRCA2 could be helpful in determining an accurate prognosis for BCA patients and for the selection of BCA patients who could potentially benefit from anti-PARP1 therapy with a combination of genotoxic chemotherapeutic agents.     

Comparison of Nitrogen Fixation for North- and South-facing <Emphasis Type="Italic">Robinia pseudoacacia</Emphasis> Stands in Central Korea

The nitrogenase activity, root nodule biomass, and rates of nitrogen (N) fixation were measured in 25-year-old pure north- and south-facing Robinia pseudoacacia stands in an urban forest of Seoul (Kkachisan Mountain) in central Korea. The nitrogenase activity was estimated using an acetylene reduction (AR) assay, which showed an increasing trend during the early growing season, with sustained high rates from June through to September with a decrease thereafter. July had the highest nitrogenase activity rate (micromoles C₂H₄ per gram dry nodule per hour), averaging 95.8 and 115.1 for the north- and south-facing stands, respectively. The maximum root nodule biomass (kilograms per hectare) was 45.7 and 9.1 for the north- and south-facing stands in July, respectively. The AR rate appeared to be strongly correlated to the soil temperature (r ² = 0.68, P < 0.001) and soil pH (r ² = 0.59, P < 0.001) while root nodule biomass was correlated to the soil temperature (r ² = 0.36, P < 0.01) and water content (r ² = 0.35, P < 0.05). The soil temperature showed clear differences between seasons, while there was a significant difference in soil pH, organic matter, total N concentrations, and available phosphorus between the north- and south-facing stands. The N₂ fixation rates during the growing season varied from 0.1 to 37.5 kg N ha⁻¹ month⁻¹ depending on the sampling location and time. The annual N₂ fixation rate (kg N per hectare per year) was 112.3 and 23.2 for the north- and south-facing stands, respectively. The differences in N₂ fixation rate between the two stands were due mainly to the differences in total nodule biomass.     

Genetic introduction of foreign genes to <Emphasis Type="Italic">Pleurotus eryngii</Emphasis> by restriction enzyme-mediated integration

Pleurotus eryngii was transformed via restriction enzyme-mediated integration. In order to construct the transformation plasmid, the enhanced cyan fluorescent protein (ECFP) gene was ligated next to the gpd promoter of the plasmid pAN7-1. Transformation was facilitated via the heat treatment of a transformation mixture containing 1 μg of the HindIII-digested plasmid DNA and 10⁶ mushroom protoplasts in 40% polyethyleneglycol solution, resulting in 10–40 hygromycin-resistant transformants. Successful transformation was evidenced by PCR, Southern blot, and confocal fluorescence microscopic analyses on the selected transformants. To date, this is the first report on the transformation of P. eryngii by REMI technique.     

Autotrophic and heterotrophic respiration in needle fir and Quercus-dominated stands in a cool-temperate forest, central Korea

To investigate annual variation in soil respiration (R _S) and its components [autotrophic (R _A) and heterotrophic (R _H)] in relation to seasonal changes in soil temperature (ST) and soil water content (SWC) in an Abies holophylla stand (stand A) and a Quercus-dominated stand (stand Q), we set up trenched plots and measured R _S, ST and SWC for 2 years. The mean annual rate of R _S was 436 mg CO₂ m⁻² h⁻¹, ranging from 76 to 1,170 mg CO₂ m⁻² h⁻¹, in stand A and 376 mg CO₂ m⁻² h⁻¹, ranging from 82 to 1,133 mg CO₂ m⁻² h⁻¹, in stand Q. A significant relationship between R _S and its components and ST was observed over the 2 years in both stands, whereas a significant correlation between R _A and SWC was detected only in stand Q. On average over the 2 years, R _A accounted for approximately 34% (range 17–67%) and 31% (15–82%) of the variation in R _S in stands A and Q, respectively. Our results suggested that vegetation type did not significantly affect the annual mean contributions of R _A or R _H, but did affect the pattern of seasonal change in the contribution of R _A to R _S.     

Influence of stand density on soil CO2 efflux for a Pinus densiflora forest in Korea

We investigated the influence of stand density [938 tree ha⁻¹ for high stand density (HD), 600 tree ha⁻¹ for medium stand density (MD), and 375 tree ha⁻¹ for low stand density (LD)] on soil CO₂ efflux (R _S) in a 70-year-old natural Pinus densiflora S. et Z. forest in central Korea. Concurrent with R _S measurements, we measured litterfall, total belowground carbon allocation (TBCA), leaf area index (LAI), soil temperature (ST), soil water content (SWC), and soil nitrogen (N) concentration over a 2-year period. The R _S (t C ha⁻¹ year⁻¹) and leaf litterfall (t C ha⁻¹ year⁻¹) values varied with stand density: 6.21 and 2.03 for HD, 7.45 and 2.37 for MD, and 6.96 and 2.23 for LD, respectively. In addition, R _S was correlated with ST (R ² = 0.77–0.80, P < 0.001) and SWC (R ² = 0.31–0.35, P < 0.001). It appeared that stand density influenced R _S via changes in leaf litterfall, LAI and SWC. Leaf litterfall (R ² = 0.71), TBCA (R ² = 0.64–0.87), and total soil N contents in 2007 (R ² = 0.94) explained a significant amount of the variance in R _S (P < 0.01). The current study showed that stand density is one of the key factors influencing R _S due to the changing biophysical and environmental factors in P. densiflora.     

Effect of carnitine on greening barley leaves

Carnitine increases chlorophyll production in greening barley leaves. [Methyl-¹⁴C]carnitine fed to greening leaves was not utilized as a carbon sou     

Protective effect of radicicol against LPS/IFN-gamma-induced neuronal cell death in rat cortical neuron-glia cultures

We investigated the protective activity of radicicol, an antifungal antibiotic, against inflammation-induced neurotoxicity in neuron-glia cultures. Radicicol potently prevented the loss of neuronal cell bodies and neurites from LPS/IFN-gamma-induced neurotoxicity in rat cortical neuron-glia cultures with an EC(50) value of 0.09 microM. Radicicol inhibited the LPS/IFN-gamma-induced expression of inducible nitric oxide synthase (iNOS) and production of nitric oxide (NO) in microglia. Additionally, radicicol decreased the LPS/IFN-gamma-induced release of tumor necrosis factor-alpha (TNF-alpha) in the cultures. The inhibitory potency of radicicol against the production of NO and TNF-alpha was well correlated with the protection of neurons. These results suggest that the protective effect of radicicol against LPS/IFN-gamma-induced neuronal cell death in neuron-glia cultures is mediated via the inhibition of TNF-alpha release, as well as the suppression of iNOS expression in microglia.