bluuebunny/crossref_metadata_2025 huggingface dataset:
Retrograde metamorphism of ultrahigh‐temperature granulites from the khondalite belt in Inner Mongolia, North China Craton: evidence from aluminous orthopyroxenes
Authors: Liu Shoujie , Bai Xiang , Li Jianghai , Santosh M.
Published: July 2010

Orthopyroxene‐sillimanite‐sapphirine‐spinel‐quartz granulites have been reported from the khondalite belt in Inner Mongolia, North China Craton (NCC), which record ultrahigh‐temperature (UHT) metamorphism. These rocks record metamorphic temperatures up to 1050°C and pressures up to 10 kbar during the peak metamorphism, as indicated by diagnostic UHT mineral assemblages such as equilibrium orthopyroxene + sillimanite + quartz, sapphirine + quartz and low‐Zn‐spinel + quartz. To well constrain the retrograde P–T conditions, we investigate orthopyroxenes in different textural settings in these UHT rocks and the results reveal marked variations in alumina contents, indicating a multistage formation. The core of coarse orthopyroxene porphyroblasts and some of the grains associated with sillimanite and quartz have the highest alumina content of up to 7.61–8.05 wt%. Rims of coarse orthopyroxene porphyroblasts and those occurring as coronas surrounding garnet grains have intermediate alumina value ranging from 6.21 to 7.61 wt%. Fine grained orthopyroxenes which form symplectite with cordierite have the lowest alumina content between 5.52 and 6.15 wt%. Based on the XAl–XMg isopleths, orthopyroxenes in different textural associations and textures indicate formation under varying temperature and pressure conditions, ranging from 950°C, 10.5 kbar to 840°C, 8.5 kbar. These results are in accordance with the P–T estimates from previous studies on these rocks using Ti‐in‐zircon geothermometry and pseudosection analysis. The reaction textures and orthopyroxene chemistry suggest an initial stage of isobaric cooling followed by isothermal decompression, and a final stage of cooling. Combined with the available age data which suggest the timing of the UHT event as 1.92 Ga, and the previous models on P–T evolution of the khondalites, our results suggest a complex exhumation of the UHT granulites within the Inner Mongolia Suture Zone associated with the final assembly of the NCC within the Columbia supercontinent during the Palaeoproterozoic. Copyright © 2010 John Wiley & Sons, Ltd.
Is rainfall intensity significant in the rainfall–runoff process within tropical rainforests of northeast Queensland? The Hewlett regression analyses revisited
Authors: Howard Andrew J. , Bonell Mike , Gilmour Don , Cassells David
Published: July 2010

Following the statistical analyses of long‐term rainfall‐runoff records from research basins in humid temperate latitudes, Hewlett and co‐workers extended the global challenge to disprove their findings that rainfall intensity was non‐significant. This paper responds to Hewlett's challenge as no preceding analyses have involved forested basins in a tropical cyclone‐prone area. Based on a 7 year rainfall‐runoff record, quickflow (QF), peak flow (QP) and quickflow response ratios (QRR) were regressed as dependent variables against rainfall parameters (intensity, Pi, amount, P), storm duration, D and antecedent flow, I. These data sets were categorised into total streamflow (Q) classes and stratified into three seasons, (monsoon, post‐monsoon and dry) for forested and cleared catchments. Where rainfall variable collinearity met acceptable levels, the addition of Pi to regression models including P, D, I contributed up to 9% and 66% of the respective variations in quickflow and peak flow. For the highest Q storm classes (monsoon), Pi alone accounted for up to 67% and 91% of the variation in QF and QP respectively and was the dominant influence on QP for all seasons. The very high rainfall intensities experienced in the monsoon season is a causal factor why these results differ from those of other research drainage basins. Surprisingly, Pi continued to have a significant influence on QF for dry season classes when less‐intense rainfall occurs. Further the results were similar for both catchments across all seasons. P was the dominant independent variable affecting QF above a threshold Q of 50 mm (monsoon), as rainfall contributes directly to saturation overland flow and return flow under saturated conditions. Further although QRR increased with increasing Q for each season, the regression results for that parameter were poor possibly due to the non‐linearity of the rainfall‐runoff relationship. Copyright © 2010 John Wiley & Sons, Ltd.
Hydrology of hillslope‐wetland streams, Polar Bear Pass, Nunavut, Canada
Authors: Young Kathy L. , Assini Jane , Abnizova Anna , De Miranda Nelson
Published: July 2010

Polar Bear Pass is a large High Arctic low‐gradient wetland (100 km2) bordered by low‐lying hills which are notched by a series of v‐shaped valleys. The spring and summer hydrology of two High Arctic hillslope‐wetland catchments, a first‐order stream, 0·2 km2 Landing Strip Creek (LSC) and a larger second‐order basin, 4·2 km2 Windy Creek (WC), is described here. A water balance framework was employed in 2008 to examine the movement of water from upland reaches into the low‐lying wetland. Snowcover was low in both basins (<50 mm in water equivalent units), but they both exhibited nival‐type regimes. After the main snowmelt season ended, runoff ceased in the smaller catchment (LSC), but not at the larger basin (WC) which continued to flow throughout the summer. Both basins responded to summer rains in different ways. At LSC, late‐summer continuous streamflow occurred only when rainfall satisfied the large soil moisture deficit in the upper bowl‐shaped zone of the basin. At WC, the presence of thinly thawed, ice‐rich polygonal terrain within the stream channel and in the upper reaches of the catchment likely limited infiltration in these near‐stream zones and enhanced runoff in response to both moderate and high rainfall. Subsequently, seasonal runoff ratios differed between the two sites (0·19 vs 0·68) as did the seasonal storage + residual (+16 vs −50 mm). This suggests that the post‐snowmelt season runoff response to summer precipitation is very much modified by the unique basin characteristics (soil‐type, vegetation, ground ice) and their location within each stream order type. Copyright © 2010 John Wiley & Sons, Ltd.
Simulation of spatiotemporal dynamics of water fluxes in Germany under climate change
Authors: Huang Shaochun , Krysanova Valentina , Österle Hermann , Hattermann Fred F.
Published: July 2010

In most of Europe, an increase in average annual surface temperature of 0·8 °C is observed, and a further increase is projected. Precipitation tends to increase in northern Europe and decrease in southern Europe, with variable trends in central Europe. The climate scenarios for Germany suggest an increase in precipitation in western Germany and a decrease in eastern Germany, and a shift of precipitation from summer to winter. When investigating the effects of climate change, impacts on water resources are among the main concerns. In this study, the first German‐wide impact assessment of water fluxes dynamics under climate change is presented in a spatially and temporally distributed manner using the state‐of‐the‐art regional climate model, Statistical Regional (STAR) model and the semi‐distributed process‐based eco‐hydrological model, soil and water integrated model (SWIM). All large river basins in Germany (lower Rhine, upper Danube, Elbe, Weser and Ems) are included. A special focus of the study was on data availability, homogeneity of data sets, related uncertainty propagation in the model results and scenario‐related uncertainty. After the model calibration and validation (efficiency from 0·6 to 0·9 in 80% of cases) the water flow components were simulated at the hydrotope level, and the spatial distributions were compared with those in the Hydrological Atlas of Germany. The actual evapotransipration is likely to increase in most parts of Germany, while total runoff generation may decrease in south and east regions. The results for the second scenario period 2051–2060 show that water discharge in all six rivers would be 8–30% lower in summer and autumn compared with the reference period, and the strongest decline is expected for the Saale, Danube and Neckar. Higher winter flow is expected in all of these rivers, and the increase is most significant for the Ems (about 18%). However, the uncertainty of impacts, especially in winter and for high water flows, remains high. Copyright © 2010 John Wiley & Sons, Ltd.
Extreme storms in Malmö, Sweden
Authors: Bengtsson Lars , Milloti Stefan
Published: July 2010

Short‐term very intensive storms in the years 1980–2007 from rain gauges in Malmö have been analysed to find intensities of long return periods and to investigate trends. Observations from different stations have been pooled into series to which probability functions have been adjusted. Quality control of short‐term precipitation records is emphasized. In order to investigate whether high rain intensities are different today compared to back in time, new and old rain data have been compared. Trends over the last 25 years have been computed for storms of duration 10 min to 1 h, and for 89 years of daily rains. A literature review of investigations of changing rain intensities is presented. It is found that 10‐ to 25‐year long rain series from single stations are too short to give good estimates of storms of long recurrence time because a single event influences much. The largest observed rains in Malmö in the investigated period have a return period of about 20–50 years. For the very short‐term storms, 50‐year old intensity–duration–frequency curves do not differ much from those derived from new data. Trend analysis shows changing short‐term high storm intensities only for storms of 10‐min duration. Copyright © 2010 John Wiley & Sons, Ltd.
Prediction of hourly actual evapotranspiration using neural networks, genetic programming, and statistical models
Authors: Izadifar Zohreh , Elshorbagy Amin
Published: July 2010

The complexity of the evapotranspiration process and its variability in time and space have imposed some limitations on previously developed evapotranspiration models. In this study, two data‐driven models: genetic programming (GP) and artificial neural networks (ANNs), and statistical regression models were developed and compared for estimating the hourly eddy covariance (EC)‐measured actual evapotranspiration (AET) using meteorological variables. The utility of the investigated data‐driven models was also compared with that of HYDRUS‐1D model, which makes use of conventional Penman–Monteith (PM) model for the prediction of AET. The latent heat (LE), which is measured using the EC method, is modelled as a function of five climatic variables: net radiation, ground temperature, air temperature, relative humidity, and wind speed in a reconstructed landscape located in Northern Alberta, Canada. Several ANN models were evaluated using two training algorithms of Levenberg–Marquardt and Bayesian regularization. The GP technique was used to generate mathematical equations correlating AET to the five climatic variables. Furthermore, the climatic variables, as well as their two‐factor interactions, were statistically analysed to obtain a regression equation and to indicate the climatic factors having significant effect on the evapotranspiration process. HYDRUS‐1D model as an available physically based model was examined for estimating AET using climatic variables, leaf area index (LAI), and soil moisture information. The results indicated that all three proposed data‐driven models were able to approximate the AET reasonably well; however, GP and regression models had better generalization ability than the ANN model. The results of HYDRUS‐1D model exhibited that a physically based model, such as HYDRUS‐1D, might be comparable or even inferior to the data‐driven models in terms of the overall prediction accuracy. Based on the developed GP and regression models, net radiation and ground temperature had larger contribution to the AET process than other variables. Copyright © 2010 John Wiley & Sons, Ltd.
Instream flow requirements for sediment transport in the lower Weihe River
Authors: Song Jinxi , Xu Zongxue , Hui Yanghe , Li Huaien , Li Qi
Published: July 2010

Estimation of instream flow requirements for sediment transport (IFRST) in the downstream Weihe River is important for the maintenance of a healthy ecosystem of the river. In this study, the IFRST for the lower Weihe River is estimated on the basis of the observed hydrological data during the period 1960–2001. The results showed that the mean annual IFRSTs for the reach between Lintong and Huaxian and the reach below Huaxian were 6·85 and 7·62 billion m3/year, respectively, and the standard errors were 0·50 and 0·76 billion m3/year, respectively. The results also showed that the Sanmenxia Reservoir is an important driver for the changes in channel morphology and hydraulics, as well as the IFRST. Furthermore, according to the hydrological frequency (p value) estimated from annual instream flow data during the period 1960–2001, four typical years (p = 25%, 50%, 75% and 90%) for the two reaches of the Weihe River were determined. The analysis showed that the IFRST has a negative power functional relationship with the sediment concentration. On the basis of the efficiency coefficients (R2) during three sub‐periods 1960–1973, 1974–1990 and 1991–2001, the annual IFRSTs in the above two reaches for the four typical years were estimated under different deposition and erosion–deposition conditions. The results provide useful references for restoration and water resource management of the Weihe River. Copyright © 2010 John Wiley & Sons, Ltd.
Do biological soil crusts determine vegetation changes in sandy deserts? Implications for managing artificial vegetation
Authors: Li X. R. , Tian F. , Jia R. L. , Zhang Z. S. , Liu L. C.
Published: July 2010

Biological soil crusts (BSCs), which are widespread in arid and semiarid regions, such as sandy deserts, strongly influence terrestrial ecosystems. Once sand‐binding vegetation has been established on sand dunes, BSCs are colonized and gradually develop from cyanobacteria dominated crusts to lichen and moss dominated crusts on dune surfaces. We conducted this study to determine if the occurrence and development of BSCs in the Tengger Desert could be used to determine sand‐binding vegetation changes via altering soil moisture and water cycling using long‐term monitoring data and field experimental observation. BSCs changed the spatiotemporal pattern of soil moisture and re‐allocation by decreasing rainfall infiltration, increasing topsoil water‐holding capacity and altering evaporation. Changes in the soil moisture pattern induced shifting of sand‐binding vegetation from xerophytic shrub communities with higher coverage (35%) to complex communities dominated by shallow‐rooted herbaceous species with low shrub coverage (9%). These results imply that BSCs can be a major factor controlling floristic and structural changes in sand‐binding vegetation and suggest that the hydrological effects of BSCs must be considered when implementing large‐scale revegetation projects in sandy deserts. Copyright © 2010 John Wiley & Sons, Ltd.
Assessing sensitivity of hydrologic responses to climate change from forested watershed in Mississippi
Authors: Parajuli Prem B.
Published: July 2010

The climatic processes such as changes in precipitation, temperature and atmospheric CO2 concentration can intensify the effects on water resources. An assessment of the effects of long‐term climate change on water resources is essential to the development of water quality improvement programs. This study was conducted in the Upper Pearl River Watershed (UPRW) in east‐central Mississippi to assess the effects of long‐term potential future climate change on average mean monthly stream flow from the five spatially distributed U. S. Geological Survey (USGS) gage stations in the UPRW using the Soil and Water Assessment Tool. The model was calibrated (January 1981 to December 1994) and validated (January 1995 to September 2008) using monthly measured stream flow data. The calibrated and validated model determined good to very good performance for stream flow prediction (R2 and E from 0·60 to 0·86) between measured and predicted stream flow values. The root mean square error values (from 14 to 37 m3 s−1) were estimated at similar levels of errors during model calibration and validation. The results showed that long‐term (50 years) average monthly stream flow sensitivity due to climate change effects was found the greatest as a result of percentage change in the precipitation followed by carbon dioxide (CO2) concentration and temperature. The long‐term model simulation scenarios as compared with the base scenario for all five spatially distributed USGS gage stations in the UPRW estimated an average monthly stream flow decrease (from 54 to 67%) and average monthly stream flow increase (from 67 to 79%) depending on the spatial characteristics of the USGS gage stations. Overall, the results indicate that the UPRW hydrology is very sensitive to potential future climate changes and that these changes could stimulate increased streamflow generation from the watershed. Copyright © 2010 John Wiley & Sons, Ltd.
Epigenetic regulation of cancer growth by histone demethylases
Authors: Lim Soyoung , Metzger Eric , Schüle Roland , Kirfel Jutta , Buettner Reinhard
Published: July 2010

Cancer is traditionally viewed as a primarily genetic disorder. However, it is now increasingly apparent that epigenetic abnormalities play a fundamental role in cancer development. Aberrant expression of histone‐modifying enzymes has been implicated in the course of tumor initiation and progression. The discovery of a large number of histone demethylases suggests an important role for dynamic regulation of histone methylation in biological processes. The observation that overexpression, amplification or mutations of several histone demethylases have been found in many types of tumors, raise the possibility of using these enzymes as diagnostic tools as well as pave a way for the discovery of novel therapeutic targets and treatment modalities. Here, we review the current knowledge of the potential role of H3K4, H3K9 and H3K27 histone demethylases in tumorigenesis.
Association between melanoma thickness, clinical skin examination and socioeconomic status: Results of a large population‐based study
Authors: Youl Philippa H. , Baade Peter D. , Parekh Sanjoti , English Dallas , Elwood Mark , Aitken Joanne F.
Published: July 2010

Survival from melanoma is inversely related to tumour thickness and is less favorable for those in lower socioeconomic (SES) strata. Reasons for this are unclear but may relate to a lower prevalence of skin screening. Our aim was to examine the association between melanoma thickness, individual‐level SES and clinical skin examination (CSE) using a population‐based case‐control study. Cases were Queensland (Australia) residents aged 20–75 years with a histologically confirmed first primary invasive cutaneous melanoma diagnosed between January 2000 and December 2003. Telephone interviews were completed by 3,762 cases (77.7%) and 3,824 (50.4%) controls. Thickness was dichotomized to thin (≤2 mm) and thick (>2 mm). Compared with controls, the risk of thick melanoma was significantly increased among men [relative risk ratio (RRR) = 1.56, 95% CI = 1.22–2.00], older participants (RRR = 1.76, 95% CI = 1.10–2.82), those educated to primary level (RRR = 1.70, 95% CI = 1.08–2.66), not married/living as married (RRR = 1.47, 95% CI = 1.15–1.88), retired (RRR = 1.39, 95% CI = 1.01–1.94) and not having a CSE in past 3 years (RRR = 1.45, 95% CI = 1.12–1.86). There was a significant trend to increasing prevalence of CSE with higher education (p < 0.01) and the benefit of CSE in reducing the risk of thick melanoma was most pronounced among that subgroup. There were no significant associations between cases with thin melanoma and controls. Melanoma thickness at presentation is significantly associated with educational level, other measures of SES and absence of CSE. Public health education efforts should focus on identifying new avenues that specifically target those subgroups of the population who are at increased risk of being diagnosed with thick melanoma.
Expression and functional role of negative signalling regulators in tumour development and progression
Authors: Murphy Tania , Hori Satoshi , Sewell James , Gnanapragasam Vincent J.
Published: July 2010

Alterations in intracellular signalling pathways such as the mitogen‐activated protein kinases (MAPKs) are key common mechanisms of tumour development and progression. As such, there has been intense research into developing drugs that can inhibit or attenuate intracellular signalling. In recent years, there has been increasing recognition that the cell already has innate negative regulatory proteins that achieve this in normal homeostasis. These regulators provide a feedback inhibitory mechanism that controls the intensity and duration of activated signalling by exogenous stimuli. Members of this group include Raf kinase inhibitor protein 1, the MAPK phosphatases, the SPROUTY and SPRED families and similar expression to FGF. A number of studies have now demonstrated significant alterations in expression of negative regulators in malignant tissue in different cancer types. In functional studies, manipulated expression of these regulators has been shown to significantly influence tumour cell behaviour and phenotype. Here, we summarise the evidence for the functional expression of negative signalling regulators in tumour growth and progression and discuss their potential role as cancer biomarkers and targets for novel drug therapy.
Warburg phenotype in renal cell carcinoma: High expression of glucose‐transporter 1 (GLUT‐1) correlates with low CD8+ T‐cell infiltration in the tumor
Authors: Singer Katrin , Kastenberger Michael , Gottfried Eva , Hammerschmied Christine G. , Büttner Maike , Aigner Michael , Seliger Barbara , Walter Bernhard , Schlösser Hans , Hartmann Arndt , Andreesen Reinhard , Mackensen Andreas , Kreutz Marina
Published: July 2010

Many tumor cells are characterized by a dysregulated glucose metabolism associated with increased glycolysis in the presence of oxygen (“Warburg Effect”). Here, we analyzed for the first time a possible link between glucose metabolism and immune cell infiltration in renal cell carcinoma (RCC). RCC specimens revealed a highly significant increase in the expression of lactate dehydrogenase A (LDHA) and glucose‐transporter 1 (GLUT‐1) compared to the corresponding normal kidney tissue on mRNA level. Accordingly, tumor cell lines of different origin such as RCC, melanoma and hepatocellular carcinoma strongly expressed LDHA and GLUT‐1 compared to their nonmalignant counterparts. In line with this finding, tumor cells secreted high amounts of lactate. High expression of GLUT‐1 and LDH5, a tetramer of 4 LDHA subunits, was confirmed by tissue microarray analysis of 249 RCC specimens. Overall, 55/79 (69.6%) and 46/71 (64.7%) cases of clear cell carcinoma showed a constitutive, but heterogeneous expression of GLUT‐1 and LDH5, respectively. The number of CD3+, CD8+ and FOXP3+ T cells was significantly elevated in RCC lesions compared to normal kidney epithelium, but effector molecules such as granzyme B and perforin were decreased in tumor infiltrating T cells. Of interest, further analysis revealed an inverse correlation between GLUT‐1 expression and the number of CD8+ T cells in RCC lesions. Together, our data suggest that an accelerated glucose metabolism in RCC tissue is associated with a low infiltration of CD8+ effector T cells. Targeting the glucose metabolism may represent an interesting tool to improve the efficacy of specific immunotherapeutic approaches in RCC.
Expression levels of hnRNP G and hTra2‐beta1 correlate with opposite outcomes in endometrial cancer biology
Authors: Ouyang Yi Qin , zur Hausen Axel , Orlowska‐Volk Marzenna , Jäger Markus , Bettendorf Herta , Hirschfeld Marc , Tong Xiao Wen , Stickeler Elmar
Published: July 2010

HnRNP G is a member of heterogeneous nuclear ribonucleoprotein (hnRNP) family with potent tumor suppressive activities. Human transformer‐2‐beta1 (hTra2‐beta1) belongs to the arginine‐serine rich like proteins and is found over‐expressed in various human cancers. It was recently shown that hnRNP G and hTra2‐beta1 exert antagonistic effects on alternative splicing. In our study we explored the impact of these two factors in tumor biology of endometrial cancer (EC). EC tissues (n = 139) were tested for hnRNP G and hTra2‐beta1 expression on mRNA level by real time PCR and on protein level by immunohistochemistry. HTra2‐beta1 mRNA level was found being induced in advanced International Federation of Gynecology and Obstetrics (FIGO) stages (p = 0.016). HnRNP G protein nuclear expression was found more prominent in patients without distant organ metastases (p = 0.033) and in FIGO Stages I/II group (p < 0.001). HTra2‐beta1 protein nuclear levels were elevated in poorly differentiated (p = 0.044) and lymph node metastases (p = 0.003) cancers. Kaplan‐Meier survival curves revealed that elevated hnRNP G mRNA (p = 0.029) and protein (p = 0.022) levels were associated with a favorable patient outcome. Multivariate Cox‐regression analyses identified nuclear hnRNP G level [hazard ratio (HR) 0.468, p = 0.026) as well as hTra2‐beta1 level (hazard ratio 5.760, p = 0.004) as independent prognostic factors for EC progression‐free survival. Our results indicate that the antagonistic functional effects of hnRNP G and hTra2‐beta1 on alternative splicing correlate directly to their opposite clinical effects on EC patient outcome.
Allele‐specific detection of K‐ras oncogene expression in human non‐small‐cell lung carcinomas
Authors: Slebos Robert J. C. , Habets Gaston G. M. , Evers Siegina G. , Mooi Wolter J. , Rodenhuis Sjoerd
Published: July 2010

Point mutations in codon 12 of the K‐ras oncogene are frequent in human lung adenocarcinomas. To study the expression of the K‐ras gene in these tumors we have developed a mRNA detection technique based on the polymerase chain reaction (PCR). By this technique, K‐ras expression can be detected semi‐quantitatively in samples of less than 100 ng total RNA. Hybridization of the amplified cDNA sequences with mutation‐specific oligonucleotides allows separate quantification of the expression of normal and point‐mutated alleles in a single sample. RNA samples from 24 human non‐small‐cell lung carcinomas (NSCLC), from 2 lung metastases of colonic adenocarcinomas, from 3 human lung adenocarcinoma cell lines, and from normal lung tissue were analyzed. In most tumors, expression of K‐ras was detected at levels equal to or several times higher than those found in normal lung tissue. A lung metastasis from a colon adenocarcinoma, known to contain an amplified K‐ras gene, highly over‐expressed the K‐ras gene. In those tumors in which the K‐ras oncogene was activated by a point mutation, both alleles of the gene were expressed. Our results show that a high over‐expression of K‐ras is a rare event in human lung carcinomas, but that a certain degree of over‐expression of the mutated allele can be demonstrated in tumors with an activated K‐ras gene. With the technique we describe here, adequate estimation of the expression of specific genes in minimal amounts of tumor cells becomes possible.
Effects of steroids on laminin‐binding integrins in a human melanoma cell line
Authors: Lopes M. T. P. , Sonohara S. , Chammas R. , Brentani M. M.
Published: July 2010

The MEL‐85 human melanoma cell line was used to investigate the effects of both estradiol and dexamethasone on expression of laminin (LM) receptors and cell adhesion capacity. Immunoblotting of eluates from whole‐cell extracts applied to LM Sepharose indicates the presence of an LM‐binding protein of 116–130 kDa that reacted with an anti‐pi integrin antibody, suggesting that the putative LM receptor of MEL‐85 cells is a member of the integrin family. Analysis of l2Sl‐LM binding to whole cells indicates the existence of low‐affinity components which display positive co‐operativity. LM‐fragment‐8 competes for this binding to the same extent as unlabelled LM (75%), while fragment PI is inactive and fibronectin (FN) competes by about 30% only. Binding of labelled fragment‐8 exhibits a pattern similar to that of intact LM. Cell adhesion to substrates coated with LM and LM fragments closely parallels binding to cells in suspension. MEL‐85 cells were estradiol‐receptor‐negative. Estradiol treatment did not stimulate LM receptor levels or attachment to LM. Growth rate also remained unaltered. To characterize the glucocorticoid dependence of MEL‐85 cells, we first established the presence of glucocorticoid receptors and an inhibitory effect on growth rate. Dexamethasone treatment resulted in marked enhancement of adhesion to LM, without alterating LM receptor number or affinity. In addition, dexamethasone changed the morphology of MEL‐85 cells in conjunction with higher LM expression as evaluated by immunofluorescence.
Increased methotrexate‐induced DNA strand breaks and cytotoxicity following mutational loss of thymidine kinase
Authors: Sano Hirohiko , Kubota Masaru , Kasai Yasufumi , Hashimoto Hisako , Shimizu Tsunehiro , Adachi Souichi , Mikawa Haruki
Published: July 2010

The cytotoxicity and DNA lesions induced by methotrexate (MTX) were compared in wild‐type, hypoxanthine‐guanine phosphoribosyltransferase‐deficient (HGPRT) and thymi‐dine‐kinase‐deficient (TK) HL‐60 cells. TK‐ and HGPRT cells were approximately 10 and 3 times more sensitive to MTX than wild‐type cells, respectively. Following incubation with 2 m̈m MTX for 16 hr, TK‐ cells showed a significantly higher number of DNA strand breaks. Concomitantly, DNA fragmentation at the nucleosomal linker region was detected more prominently in TK‐ cells. Although MTX tended to decrease TTP pools similarly in all 3 cell types, the initial TTP level in TK‐ cells was only about one‐fifth of that found in the wild type. These results indicate that the thymidine salvage pathway has a pivotal role in mediating MTX‐induced toxicity and DNA lesions.
Therapeutic effectiveness against mopc—315 plasmacytoma of low or high doses of the synthetic thymic hormone THF—γ2 in combination with an “immunomodulating” or a “non—immunomodulating” drug
Authors: Ophir R. , Pecht M. , Burstein Y. , Harshemesh H. , Ben‐Efraim S. , Trainin N.
Published: July 2010

We reported previously that treatment of mice bearing MOPC—315 plasmacytoma with the drugs L—PAM (phenylalanine mustard) or S—FU (5—fluorouradl), in combination with low doses of THF—γ2, was more effective in increasing their survival time than treatment with the drug alone. We show here that in the combined treatment using a single injection of S—FU followed by multiple (8–15) injections of THF—γ2, the megadoses were more effective than the low doses in increasing the survival time of MOPC—315 tumor—bearing mice. On the other hand, in combination with L—PAM, both low and high doses of THF—γ2 were equally effective. The need for high doses of THF—γ2, when used in combination with 5—FU, could be due to the fact that 5—FU acts as a “non—immuno—modulating” drug and has to be used at a high, immunosuppressive dose.
The role of G‐protein in matrix‐mediated motility of highly and poorly invasive melanoma cells
Authors: Lester Bruce R. , Weinstein Lee S. , McCarthy James B. , Sun Zhengqi , Smith Ron S. , Furcht Leo T.
Published: July 2010

Membranes from 2 K1735 murine melanoma clones of high invasive capacity show increased amounts of pertussis toxin (PT) substrate when compared to a weakly invasive cellular counterpart. Using a panel of specific G‐protein antibodies, we identified Giα2 as the PT‐sensitive G‐protein uniquely abundant in highly invasive cells. In addition, RNA hybridization results confirm the immunoblot observations that Giα2 is present at higher levels in strongly invasive cells. This result suggests that the elevated expression of Giα2 in highly invasive cells is not entirely due to differences in either translational efficiency or protein degradation but is related to altered RNA transcriptional initiation, processing and/or degradation. ADP‐ribosylation of G1 α‐subunits by PT inhibited the fi‐bronectin, laminin and collagen type‐IV‐stimulated motility of the 2 highly invasive clones, while PT treatment of cells from a poorly invasive clone resulted in little or no reduction of the fibronectin, laminin or collagen type‐IV‐stimulated lower motility. Furthermore, PT treatment of highly or poorly invasive KI735 clones does not result in any alteration in cellular cAMP accumulation, suggesting that the PT substrate is not linked with the adenylyl cyclase enzyme complex. The data suggest that a PT‐sensitive G‐protein, probably Giα2, regulates second messenger pathways that contribute to elevated motility in highly invasive KI735 cells.
Vascularity, perfusion rate and local tissue oxygenation of tumors derived from rus‐transformed fibroblasts
Authors: Kaixinowski F. , Wilkerson R. , Moore R. , Strauss W. , Vaupel P.
Published: July 2010

Tumors derived from ras‐transformed rat fibroblasts were investigated in order to gain insight into possible interrelationships between oncogenic transformations and therapeutically relevant parameters of the metabolic micromilieu of solid tumors in vivo. Tumors grew in nude mice after injection of in vitro‐passaged cells. Growth rates, early stages of angiogenesis, perfusion and tissue oxygenation were assessed. Compared with the parental cell line, both ras transformants grew very rapidly and exhibited an early onset of angiogenesis. Perfusion rates of one ras‐transformed tumor line were similar to those of the parental tumors whereas reduced flow values were detected in tumors of the other rats line. The better perfused tumors exhibited more adequate tissue oxygen levels whereas reduced oxygen levels were obvious in the poorly perfused ras line. These results indicate that ras transformation alters therapeutically relevant parameters of the tumor micromilieu. However, the tumor phenotype cannot be predicted even if the transforming oncogene is known.
Clonal dominance of select subsets of viral kirsten ras+‐transformed 3T3 cells during tumor progression
Authors: Radinsky Robert , Culp Lloyd A.
Published: July 2010

Long‐term culturing of viral Kirsten‐ras‐oncogene (v‐Ki‐ras)‐transformed BALB/c 3T3 cells (KiMSV) selectively enriches for cells which have deleted the viral oncogene. In contrast, v‐Ki‐ras in vivo is amplified and expression increased in all late‐stage tumors and lung metastases relative to late‐passage KiMSV cells being injected. The nature and significance of these selection processes, in terms of the v‐Ki‐ras gene, have been explored using genetically‐tagged cells, as have the properties of v‐Ki‐ras‐ revertant subclones. Inoculation of KiMSV late‐passage cells (containing ≤5% v‐Ki‐ras+ cells) into nude mice, generated primary and lung metastatic tumors with the v‐Ki‐ras gene at increased dosage in all tumors and their single‐cell clones, isolated at both early and late stages of tumor development; this demonstrates early and specific in vivo selection for v‐Ki‐ras+ cells in both induction and progression of tumors in this system. v‐Ki‐ras‐ revertant subclones, isolated from late‐passage KiMSV cells and inoculated individually into athymic nude mice, yielded tumors for only I of the 4 revertants, with no evidence for v‐Ki‐ras sequences in these tumor cells, thereby revealing a v‐Ki‐ras‐independent mechanism for tumor formation in a small subset of revertant cells. Mixtures of the 4 subclones yielded tumors in all animals, although at a much longer latent period than observed with v‐Ki‐ras+ cells. Experiments with mixtures of v‐Ki‐ras‐ revertant cells and pSV2neo‐tagged/v‐Ki‐ras+ cells (both complex NeoR cell mixtures and individual Neo clones tested) at various cell ratios revealed clonal variability among v‐Ki‐ras+ cells for dominance during tumor formation. Moreover, the complex Neo cell mixtures yielded both primary and metastatic tumors with simplified patterns of pSV2neo integration sites, suggesting that secondary genetic or epigenetic events, in addition to v‐Ki‐ras, contribute to the tumor‐progressing phenotype. These experiments taken together demonstrate (a) clone‐specific early selection of distinct v‐Ki‐ras+ cells amongst themselves and over v‐Ki‐ras‐ cells in both induction and progression of tumors, (b) reduced tumorigenic competence of v‐Ki‐ras‐ revertant cells, with a small subset displaying a v‐Ki‐ras‐independent mechanism for tumor formation in this BALB/c 3T3 system, and (c) the significance of additional genetic or epigenetic events for tumor‐progressing competence in unique subsets of v‐Ki‐ras+ cells.
Definition of the expression of the human carcinoembryonic antigen and non‐specific cross‐reacting antigen in human breast and lung carcinomas
Authors: Robbins Paul F. , Eggensperger Diane , Qi Chen‐Feng , Schlom Jeffrey
Published: July 2010

Mouse cell lines transfected with carcinoembryonic antigen (CEA) and with 2 other members of the human CEA gene family, non‐specific cross‐reacting antigen (NCA) and biliary glycoprotein (BGP), were used to analyze the specificity of several monoclonal antibodies (MAbs). MAbs COL‐1 and COL‐6 were shown to react with the transfected CEA gene product but not with NCA, confirming previous results. Cells expressing the transfected BGP gene product also failed to react with COL‐1 and COL‐6. The MAb B6.2 reacted with cells expressing the NCA gene product but not with those expressing CEA or BGP. The MAb B1.1 reacted strongly with the transfected CEA and BGP gene products but only weakly with the NCA gene product. These antibodies were then utilized in the histochemical analysis of a number of primary and secondary breast and lung tumors. The results indicate that a majority of breast and lung tumors express CEA, and nearly all breast and lung tumors express NCA. Fairly homogeneous expression of CEA and NCA was seen in the majority of both breast and lung tumors. Our results indicate that CEA may be an important target for immunotherapy in a large number of patients with breast and lung tumors.
Prevalence of HPV in cytomorphologically normal cervical smears, as determined by the polymerase chain reaction, is age‐dependent
Authors: Melkert Peter W. J. , van den Brule Adriaan J.C. , Risse Elle K. J. , van Diest Paul J. , Meijer Chris J. L. M. , Walboomers Jan M. M. , Helmerhorst Theo , Hopman Ellen , Bleker Otto P. , Schipper Marguérite E. I.
Published: July 2010

The prevalence of human papillomavirus (HPV) genotypes in relation to age was investigated by the polymerase chain reaction (PCR) method in cytologically normal smears from 4 different groups of women. Group A consisted of young women from a district population, aged 15–34 years, using oral contraceptives and visiting general practitioners for a check‐up (n = 156); group B were asymptomatic women, aged 35–55, in a district population participating in a triennial screening program for cervical cancer (n = 1555); group C and D consisted of women, seen at the gynecological outpatient department for a wide spectrum of gynecological complaints or for control of their hormonal contraception, aged 15–34 years (n = 2320), and aged 35–55 years (n = 1826) respectively. An HPV (all types) prevalence of 14.1%, 4.1%, 13.9% and 6.6% and an HPV 16/18 prevalence of 3.8%, 0.9%, 3.3% and 1.5% were found in groups A, B, C and D respectively. Statistically significant differences (p value <0.001) in HPV prevalence were found between women aged 15–34 years and women aged 35–55 years in the district population and in the hospital population. No statistically significant differences in HPV 16/18 were observed after age‐matching between women in corresponding age‐classes of both populations. In a 5‐year interval analysis a strong age‐dependent relationship was demonstrated, with a maximum between 20 and 24 years. After the age of 35 a constant level of 1–2% HPV 16/18 was observed. These results indicate that genital HPV infections are age‐dependent and suggest that HPV infections at young age can be transient. The implications of these findings in the context of cervical cancer screening are discussed.
Expression of the different viral mRNAs of human papilloma virus 6 in a squamous‐cell carcinoma of the bladder and the cervix
Authors: Oft M. , Böhm S. , Iftner T. , Wilczynski S. P.
Published: July 2010

The prevalence of HPV6 and HPV11 in benign condylomata or mild dysplasias has led to the view of HPV6/11 as rather harmless viruses in relation to carcinogenesis. However, the detection of HPV6/11 DNA in a number of individual cases of squamous‐cell carcinomas of the anogenital/urinary tract could also point to a possible contribution of these viruses in the development of certain malignancies. Recently we have shown that the transcription of the E6 and E7 genes of HPV6 in benign anogenital condylomata is strictly confined to the basal cell layers of the epithelium, which express c‐fos mRNA. This report describes the in situ hybridization analysis of individual mRNA species of HPV6 in 2 malignant tumours. A consistent feature of both carcinomas was the lack of detectable amounts of E6 mRNA, while the E7 mRNA was the major transcript observed. In situ hybridization with a riboprobe for c‐fos revealed an expression pattern similar to that detected with the E7 probe. Hybridization with a probe specific for mRNA with a coding potential for a full‐length E2 protein yielded weak signals in both carcinomas. Using restriction‐enzyme analysis, we compared the long control region of HPV6 amplified by polymerase chain reaction from both tumours with already known HPV6 subtypes. In contrast to previous reports suggesting a correlation between genetic alterations in the long control region of HPV6 and increased malignant behaviour, our data do not support this hypothesis.
Interleukin 7 enhances the proliferation and effector function of tumor‐infiltrating lymphocytes from renal‐cell carcinoma
Authors: Sica Dante , Rayman Patricia , Stanley Jill , Finke James H. , Klein Eric , Klein Eric , Edinger Mark , Tubbs Raymond R. , Bukowski Ronald
Published: July 2010

Previous studies have documented the effects of IL2 on the growth and effector function of tumor‐infiltrating lymphocytes (TIL) in cancer patients. Since IL7 is known to induce T‐ and NK‐cell responses in the peripheral blood, we examined the immuno‐enhancing effects of IL7 on TIL derived from human renal‐cell carcinoma (RCC). Whereas IL2 induced the growth of freshly isolated TIL in vitro, IL7 was ineffective alone and failed to increase the total number of cells proliferating to IL2. However, IL7 did provide a proliferative signal to TIL that were initially expanded in culture with either IL2 or IL2/IL7 for 2 weeks. IL7 also induced the proliferation of CD4+ and CD8+ TIL lines that have specificity for RCC. The proliferative response induced by IL7 was independent of IL2, since anti‐IL2 antibodies did not block IL7‐induced proliferation of TIL. IL7 did cooperate with anti‐CD3 stimulation for the induction of proliferation; however, the magnitude of this interaction was variable and the response usually additive. In addition, IL7 synergized with anti‐CD3 to induce the secretion of IFNγ from short‐term‐cultured TIL and from a TIL line. Although IL7 did not promote the development of a tumor‐specific T‐cell response from IL2‐expanded TIL, IL7 enhanced lymphokine‐activated killer (LAK) activity from some short‐term‐cultured TIL. These results illustrate that IL7 can potentiate the growth and production of IFNγ from RCC‐reactive TIL and, to a lesser extent, enhance IL2‐induced LAK activity of TIL.
Shedding of GD2 ganglioside in patients with retinoblastoma
Authors: Portoukalian Jacques , David Marie‐Jeanne , Richard Michel , Gain Philippe
Published: July 2010

Retinoblastoma is a rare tumor of the young child with an intraocular localization that leads to certain problems of diagnosis. With the aim of defining a biochemical marker—which is still lacking for this disease—the gangliosides of a pool of fresh retinoblastoma tumors were analyzed. The ganglioside pattern was shown to have GM3, GM2, GM1, GD3, GD2, GD1b and GT1b as the major components. The occurrence of a high concentration of GD2 in the tumors led us to investigate the possibility of changes in the level of GD2 in the sera of retinoblastoma patients, using quantitative immunostaining with GD2‐specific mouse monoclonal antibodies (MAbs). In 9 out of 10 tumor‐bearing patients, the serum level of GD2 ganglioside was significantly higher than the average value found in normal individuals. A 2‐year follow‐up of patients showed that successful treatment resulted in a rapid decrease in the serum level of GD2 down to the normal range, from which a subsequent elevation was seen only in relapsing patients. Although the clinical study needs further development, the results obtained to date suggest that GD2 is shed in the serum of tumor‐bearing patients and that the level of GD2 could be a potential serum marker of human retinoblastoma.
Involvement of p53 gene mutations in human endometrial carcinomas
Authors: Honda Tsuyoshi , Kato Hidenori , Imamura Toshiro , Gima Tomonao , Nishida Jun‐Ichi , Sasaki Masahiro , Wake Norio , Hoshi Kazuhiko , Sato Akira
Published: July 2010

Mutations in the p53 gene are associated with a wide variety of human malignancies. Point mutation in one allele and loss of the remaining one generally lead to inactivation of p53 protein. A high frequency of allelic losses corresponding to the 17p13.3 region that contained the p53 gene sequence was also noted in human endometrial carcinoma. Thus, in order to confirm involvement of the p53 gene in endometrial carcinogenesis, we searched for nucleotide sequence change in this gene in 42 endometrial carcinomas that had been subjected to previous LOH analyses. Using the polymerase‐chain‐reaction‐single‐strand conformation polymorphism (PCR‐SSCP) method, we detected p53 gene mutations in 4 specimens. Two adenocarcinomas with allelic loss on 17p contained a mutant p53 gene in the allele that was retained. One specimen with a p53 gene mutation contained a 17q deletion but was uninformative for LOH on 17p. p53 gene mutation was also noted in the remaining stage‐1 carcinoma, though the 17p deletion was not detected in the previous LOH examination. However, 5 specimens with the LOH on 17p retained the wild‐type p53 gene. In the remaining 33 specimens, both alleles of p53 gene seemed to be normal. The mutations observed in 2 specimens (cases 10 and 24), involving C‐to‐T and T‐to‐G substitutions, were located in a highly conserved region. However, the mutations identified in the remaining 2 cases (29 and 35) were at regions positioned outside conserved stretches.