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Transmutation detectors (TMDs) are based on a similar principle as neutron activation detectors (NADs). In both cases, the neutron fluence is estimated from the number of reactions in the detectors. The main differences between these two detectors are the type of product created by the nuclear reaction and the evaluation of the irradiated detectors. In TMD, the transmuted nuclide is stable, and the number of reactions is gained by analytical methods suitable for measuring low concentrations. In NAD, the nuclear reaction leads to the production of radionuclides and the number of reactions is evaluated from the activity measured by radiometric instruments. While TMDs for thermal neutrons can be easily prepared and evaluated due to their high thermal neutron cross sections for isotopes such as 10B, 115In or 197Au, the requirements for fast neutron TMDs are higher. Cross sections for nuclear reactions suitable for the TMD method with fast neutrons are in the range of 1 to 100 mb for the fission spectrum. This leads to concentrations from 0.01 ppm to 1 ppm for fast neutron fluence of 1E19 cm-2. These low concentrations imply requirements for detector material purity and sensitivity of concentration evaluation equipment. Materials for fast neutron TMDs were proposed, where the relevant parameters, such as energy threshold and minimal detectable fluence are known and convenient. An experimental comparison of some TMD and NAD responses was made in the LVR-15 research reactor using secondary ion mass spectrometry to evaluate the concentration of TMDs.

On September 26th, 2022, the detonations at the gas pipelines Nord Stream 1 and 2 resulted in some of the largest non-natural releases of methane known. The distribution of methane in the surrounding seawater and the possible effects were not apparent. To trace the pathways of methane we recorded CH 4 concentrations and the isotopic signal (δ 13 C-CH 4 ) in seawater, and air. A week post-explosion, we detected methane concentrations up to 4 orders of magnitude above the natural Baltic Sea background. The released fossil methane created a distinct plume with δ 13 C-CH 4 ratios differing from natural background values. The strong water stratification preserved the distribution pattern initiated by the explosion, shown by the laterally strong concentration gradient within the plume. Our analysis encompasses three stages of the explosion's impact; the initial sea-air methane release, measurements taken during our research expedition one week later, and a third stage triggered by the shift from summer to winter conditions as an outlook on how winter mixing and microbial activity will influence the plume., (© 2024. The Author(s).)

Dysregulation of the BCL-2 family is implicated in protecting chronic myeloid leukemia (CML) cells from intracellular damage and BCR::ABL1-inhibition with tyrosine kinase inhibitors (TKIs) and may be a viable therapeutic target in blast phase (BP-)CML, for which treatment options are limited. BH3 mimetics, a class of small molecule inhibitors with high-specificity against the prosurvival members of the BCL-2 family, have displayed clinical promise in the treatment of chronic lymphocytic and acute myeloid leukemia as single agents and in combination with standard-of-care therapies. Here we present the first comparison of inhibition of BCL-2 prosurvival proteins BCL-2, BCL-xL and MCL-1 in combination with a second or third generation TKI, crucially with comparisons drawn between myeloid and lymphoid BP-CML samples. Co-treatment of four BP-CML cell lines with the TKIs nilotinib or ponatinib and either BCL-2 (venetoclax), MCL-1 (S63845) or BCL-xL (A-1331852) inhibitors resulted in a synergistic reduction in cell viability and increase in phosphatidylserine (PS) presentation. Nilotinib with BH3 mimetic combinations in myeloid BP-CML patient samples triggered increased induction of apoptosis over nilotinib alone, and a reduction in colony-forming capacity and CD34 + fraction, while this was not the case for lymphoid BP-CML samples tested. While some heterogeneity in apoptotic response was observed between cell lines and BP-CML patient samples, the combination of BCL-xL and BCR::ABL1 inhibition was consistently effective in inducing substantial apoptosis. Further, while BH3 mimetics showed little efficacy as single agents, dual-inhibition of BCL-2 prosurvival proteins dramatically induced apoptosis in all cell lines tested and in myeloid BP-CML patient samples compared to healthy donor samples. Gene expression and protein level analysis suggests a protective upregulation of alternative BCL-2 prosurvival proteins in response to BH3 mimetic single-treatment in BP-CML. Our results suggest that BH3 mimetics represent an interesting avenue for further exploration in myeloid BP-CML, for which alternative treatment options are desperately sought., (© 2022. The Author(s).)

In our mouse model, gastric acid-suppression is associated with antigen-specific IgE and anaphylaxis development. We repeatedly observed non-responder animals protected from food allergy. Here, we aimed to analyse reasons for this protection. Ten out of 64 mice, subjected to oral ovalbumin (OVA) immunizations under gastric acid-suppression, were non-responders without OVA-specific IgE or IgG1 elevation, indicating protection from allergy. In these non-responders, allergen challenges confirmed reduced antigen uptake and lack of anaphylactic symptoms, while in allergic mice high levels of mouse mast-cell protease-1 and a body temperature reduction, indicative for anaphylaxis, were determined. Upon OVA stimulation, significantly lower IL-4, IL-5, IL-10 and IL-13 levels were detected in non-responders, while IL-22 was significantly higher. Comparison of fecal microbiota revealed differences of bacterial communities on single bacterial Operational-Taxonomic-Unit level between the groups, indicating protection from food allergy being associated with a distinct microbiota composition in a non-responding phenotype in this mouse model., (Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.)

The transcription factor grainyhead-like 2 (GRHL2) plays a crucial role in various developmental processes. Although GRHL2 recently has attracted considerable interest in that it could be identified as a novel suppressor of the epithelial-to-mesenchymal transition, evidence is emerging that GRHL2 also exhibits tumour-promoting activities. Aim of the present study therefore was to help defining the relevance of GRHL2 for human cancers by performing a comprehensive immunohistochemical analysis of GRHL2 expression in normal (n = 608) and (n = 3,143) tumour tissues using tissue microarrays. Consistent with its accepted role in epithelial morphogenesis, GRHL2 expression preferentially but not exclusively was observed in epithelial cells. Regenerative and proliferating epithelial cells with stem cell features showed a strong GRHL2 expression. Highly complex GRHL2 expression patterns indicative of both reduced and elevated GRHL2 expression in tumours, possibly reflecting potential tumour-suppressing as well as oncogenic functions of GRHL2 in distinct human tumours, were observed. A dysregulation of GRHL2 expression for the first time was found in tumours of non-epithelial origin (e.g., astrocytomas, melanomas). We also report GRHL2 copy number gains which, however, did not necessarily translate into increased GRHL2 expression levels in cancer cells. Results obtained by meta-analysis of gene expression microarray data in conjunction with functional assays demonstrating a direct regulation of HER3 expression further point to a potential therapeutic relevance of GRHL2 in ovarian cancer. Hopefully, the results presented in this study may pave the way for a better understanding of the yet largely unknown function of GRHL2 in the initiation, progression and also therapy of cancers., (© 2015 UICC.)

Disseminated tumor cells (DTC), which share mesenchymal and epithelial properties, are considered to be metastasis-initiating cells in breast cancer. However, the mechanisms supporting DTC survival are poorly understood. DTC extravasation into the bone marrow may be encouraged by low oxygen concentrations that trigger metabolic and molecular alterations contributing to DTC survival. Here, we investigated how the unfolded protein response (UPR), an important cytoprotective program induced by hypoxia, affects the behavior of stressed cancer cells. DTC cell lines established from the bone marrow of patients with breast cancer (BC-M1), lung cancer, (LC-M1), and prostate cancer (PC-E1) were subjected to hypoxic and hypoglycemic conditions. BC-M1 and LC-M1 exhibiting mesenchymal and epithelial properties adapted readily to hypoxia and glucose starvation. Upregulation of UPR proteins, such as the glucose-regulated protein Grp78, induced the formation of filamentous networks, resulting in proliferative advantages and sustained survival under total glucose deprivation. High Grp78 expression correlated with mesenchymal attributes of breast and lung cancer cells and with poor differentiation in clinical samples of primary breast and lung carcinomas. In DTCs isolated from bone marrow specimens from breast cancer patients, Grp78-positive stress granules were observed, consistent with the likelihood these cells were exposed to acute cell stress. Overall, our findings provide the first evidence that the UPR is activated in DTC in the bone marrow from cancer patients, warranting further study of this cell stress pathway as a predictive biomarker for recurrent metastatic disease., (©2015 American Association for Cancer Research.)

Using a retrovirus-mediated cDNA expression cloning approach, we identified the grainyhead-like 2 (GRHL2) transcription factor as novel protooncogene. Overexpression of GRHL2 in NIH3T3 cells induced striking morphological changes, an increase in cell proliferation, anchorage-independent growth, and tumor growth in vivo. By combining a microarray analysis and a phylogenetic footprinting analysis with various biochemical assays, we identified the epidermal growth factor receptor family member Erbb3 as a novel GRHL2 target gene. In breast cancer cell lines, shRNA-mediated knockdown of GRHL2 expression or functional inactivation of GRHL2 using dominant negative GRHL2 proteins induces down-regulation of ERBB3 gene expression, a striking reduction in cell proliferation, and morphological and phenotypical alterations characteristic of an epithelial-to-mesenchymal transition (EMT), thus implying contradictory roles of GRHL2 in breast carcinogenesis. Interestingly, we could further demonstrate that expression of GRHL2 is directly suppressed by the transcription factor zinc finger enhancer-binding protein 1 (ZEB1), which in turn is a direct target for repression by GRHL2, suggesting that the EMT transcription factors GRHL2 and ZEB1 form a double negative regulatory feedback loop in breast cancer cells. Finally, a comprehensive immunohistochemical analysis of GRHL2 expression in primary breast cancers showed loss of GRHL2 expression at the invasive front of primary tumors. A pathophysiological relevance of GRHL2 in breast cancer metastasis is further demonstrated by our finding of a statistically significant association between loss of GRHL2 expression in primary breast cancers and lymph node metastasis. We thus demonstrate a crucial role of GRHL2 in breast carcinogenesis.

Differentiated mammary epithelium shows apicobasal polarity, and loss of tissue organization is an early hallmark of breast carcinogenesis. In BRCA1 mutation carriers, accumulation of stem and progenitor cells in normal breast tissue and increased risk of developing tumors of basal-like type suggest that BRCA1 regulates stem/progenitor cell proliferation and differentiation. However, the function of BRCA1 in this process and its link to carcinogenesis remain unknown. Here we depict a molecular mechanism involving BRCA1 and RHAMM that regulates apicobasal polarity and, when perturbed, may increase risk of breast cancer. Starting from complementary genetic analyses across families and populations, we identified common genetic variation at the low-penetrance susceptibility HMMR locus (encoding for RHAMM) that modifies breast cancer risk among BRCA1, but probably not BRCA2, mutation carriers: n = 7,584, weighted hazard ratio ((w)HR) = 1.09 (95% CI 1.02-1.16), p(trend) = 0.017; and n = 3,965, (w)HR = 1.04 (95% CI 0.94-1.16), p(trend) = 0.43; respectively. Subsequently, studies of MCF10A apicobasal polarization revealed a central role for BRCA1 and RHAMM, together with AURKA and TPX2, in essential reorganization of microtubules. Mechanistically, reorganization is facilitated by BRCA1 and impaired by AURKA, which is regulated by negative feedback involving RHAMM and TPX2. Taken together, our data provide fundamental insight into apicobasal polarization through BRCA1 function, which may explain the expanded cell subsets and characteristic tumor type accompanying BRCA1 mutation, while also linking this process to sporadic breast cancer through perturbation of HMMR/RHAMM., Competing Interests: The authors have declared that no competing interests exist.

The activated leukocyte cell adhesion molecule (ALCAM) is overexpressed in many mammary tumors, but controversial results about its role and prognostic impact in breast cancer have been reported. Therefore, we evaluated the biologic effects of ALCAM expression in two breast cancer cell lines and a larger cohort of mammary carcinomas. By stable transfections, MCF7 cells with ALCAM overexpression and MDA-MB231 cells with reduced ALCAM levels were generated and analyzed in functional assays and cDNA microarrays. In addition, an immunohistochemical study on 347 patients with breast cancer with long-term follow-up and analysis of disseminated tumor cells (DTCs) was performed. In both cell lines, high ALCAM expression was associated with reduced cell motility. In addition, ALCAM silencing in MDA-MB231 cells resulted in lower invasive potential, whereas high ALCAM expression was associated with increased apoptosis in both cell lines. Among genes which were differentially expressed in clones with altered ALCAM expression, there was an overlap of 15 genes between both cell lines, among them cathepsin D, keratin 7, gelsolin, and ets2 whose deregulation was validated by western blot analysis. In MDA-MB231 cells, we observed a correlation with VEGF expression which was validated by enzyme-linked immuno sorbent assay (ELISA). Our IHC results on primary breast carcinomas showed that ALCAM expression was associated with an estrogen receptor-positive phenotype. In addition, strong ALCAM immunostaining correlated with nodal involvement and the presence of tumor cells in bone marrow. By Kaplan-Meier analysis, strong ALCAM expression in ductal carcinomas correlated with shorter recurrence-free intervals (P=0.048) and overall survival (OAS, P=0.003). Our results indicate that the biologic role of ALCAM in breast cancer is complex, but overexpression might be relevant for outcome in ductal carcinomas.

Many cancer-associated genes remain to be identified to clarify the underlying molecular mechanisms of cancer susceptibility and progression. Better understanding is also required of how mutations in cancer genes affect their products in the context of complex cellular networks. Here we have used a network modeling strategy to identify genes potentially associated with higher risk of breast cancer. Starting with four known genes encoding tumor suppressors of breast cancer, we combined gene expression profiling with functional genomic and proteomic (or 'omic') data from various species to generate a network containing 118 genes linked by 866 potential functional associations. This network shows higher connectivity than expected by chance, suggesting that its components function in biologically related pathways. One of the components of the network is HMMR, encoding a centrosome subunit, for which we demonstrate previously unknown functional associations with the breast cancer-associated gene BRCA1. Two case-control studies of incident breast cancer indicate that the HMMR locus is associated with higher risk of breast cancer in humans. Our network modeling strategy should be useful for the discovery of additional cancer-associated genes.

Extracellular matrix metalloproteinase inducer expressed by tumor cells stimulates peritumoral fibroblasts to produce matrix metalloproteinases, thus contributing to tumor invasion and metastasis. To assess its suitability as potential therapeutic target, the overall incidence of EMMPRIN expression in normal and neoplastic tissues was analyzed. EMMPRIN expression was detected immunohistochemically using monoclonal antibodies MEM-M6/1 and HIM6 and tissue microarrays with 2,348 and 608 tissue samples from 129 distinct tumor types and 76 different normal tissues, respectively. Expression and glycosylation state of EMMPRIN in human breast cancer cells were analyzed by Western blot analysis with monoclonal antibodies recognizing distinct carbohydrate structures and biochemical methods. EMMPRIN expression was found in 112 of 129 tumor entities analyzed with malignant tumors being EMMPRIN positive more frequently than benign tumors. A remarkable heterogeneity in EMMPRIN expression between tumor entities was observed. Among others, squamous-cell carcinomas (60-100%), pancreatic (87%), chromophobic kidney (83%), hepatocellular (83%) or medullary breast (83%) adenocarcinomas as well as glioblastoma multiforme (79%) presented with a particular high incidence of EMMPRIN expression. There were a limited number of EMMPRIN-positive normal cell types including proliferatively active and differentiating epithelial cells, germ cells, myocardial cells in the left heart ventricle or vascular endothelial cells of the brain. We could further demonstrate that breast cancer cells expressed EMMPRIN isoforms differing in the presence or absence of Lewis X glycan structures. Our results may assist in defining the suitability of EMMPRIN as therapeutic target and predicting negative side effects., (Copyright 2006 Wiley-Liss, Inc.)

Purpose: The bone marrow is a frequent and clinically important homing site for early disseminated breast cancer cells. Here, we aimed to profile the protein expression of these cells using unique cell line models and to evaluate the prognostic relevance of candidate gene expression for breast cancer patients., Experimental Design: To identify expression patterns characteristic for micrometastatic cells, three different cell lines (BC-K1, BC-P1, and BC-S1) established by SV40 immortalization of cancer cells isolated from the bone marrow of patients with breast cancer were compared with MCF-7 breast cancer and SV40 immortalized normal breast ductal cells (MTSV-1.7) using two-dimensional gel electrophoresis followed by MALDI-ToF analysis. The prognostic significance and clinicopathologic associations of selected differentially expressed proteins were evaluated using high-density breast cancer tissue microarrays., Results: In contrast to MCF-7 and MTSV1-7 reference cell lines, all micrometastatic cancer cell lines displayed loss of epithelial cytokeratins (CK8, CK18, and CK19) and ectopic expression of vimentin commonly present in mesenchymal cells. Immunohistochemical analysis of 2,517 samples of breast cancer further showed that loss of cytokeratin and ectopic vimentin expression were significantly associated with a higher tumor grade, high mitotic index, and negative estrogen/progesterone-receptor status. Although in univariate analyses significantly related to clinical outcome, none of the cytokeratins analyzed were independently associated with either overall or cancer-specific survival., Conclusions: Micrometastatic cancer cells exhibit marked changes in the expression pattern of cytoskeletal proteins indicative of an epithelial-mesenchymal transition. This phenotypical change could already be detected in primary tumors and is associated with the aggressive behavior of breast cancer cells in vivo.

Purpose: EMMPRIN (extracellular matrix metalloprotease inducer) is a glycosylated member of the immunoglobulin superfamily known to stimulate the production of matrix metalloproteases (MMPs) 1, 2, and 3 and MT1-MMP in peritumoral fibroblasts. We here evaluated whether EMMPRIN expression is related to tumor progression in human breast cancer., Experimental Design: An immunohistochemical study using high-density tissue microarrays (n = 2222 breast cancer samples) and EMMPRIN-specific antibodies HIM6 and MEM-M6/1 was performed, and staining results were statistically correlated with various clinicopathological parameters. To analyze the putative association between EMMPRIN expression and bone marrow (BM) micrometastasis, an additional set of 55 breast tumors from patients with or without micrometastatic cells as determined with anti-cytokeratin antibody A45-B/B3 were included in our study. Cytokeratin-positive cells in BM were costained with EMMPRIN-specific antibody 1G6.2., Results: Positive EMMPRIN staining correlated significantly with various histopathological risk factors (higher tumor grade, increased tumor size, negative estrogen receptor status and progesterone receptor status, and higher mitotic index) as well as decreased tumor-specific survival (log-rank, P = 0.0027). In particular, in patients > 50 years (i.e., postmenopausal women), EMMPRIN expression was an independent prognosticator as shown by Cox regression analysis (relative risk = 1.7, 95% confidence interval 1.4-4.3, P = 0.036). An involvement of EMMPRIN in tumor progression was also supported by the fact that it was expressed on approximately 90% of micrometastatic cells in BM., Conclusions: EMMPRIN expression in primary tumor predicts an unfavorable prognosis in breast cancer, suggesting a crucial role of EMMPRIN in progression of human mammary carcinomas.

Hyaluronan or hyaluronic acid (HA) is a normal component of mammalian follicular, oviduct, and uterine fluids. Granulosa and expanding cumulus cells secrete large amounts of HA, and when HA is added in maturation and culture media, it improves the developmental potential of oocytes and embryos. HA regulates gene expression, signaling, proliferation, motility, adhesion, and morphogenesis. Many of these biological activities of HA are mediated through binding to the receptor for HA-mediated motility/intracellular HA-binding protein (RHAMM/IHABP). We evaluated the presence and dynamics of RHAMM/IHABP mRNA and protein expression in different stages of in vitro-produced bovine embryos using quantitative reverse transcriptase-real time-polymerase chain reaction and immunohistochemistry. We also analyzed the effects of different culture systems on the relative abundance of RHAMM/IHABP transcripts. RHAMM/IHABP mRNA levels decreased from the 2-cell to the 16-cell stage, increased again at the morula stage, and reached their highest level at the expanded blastocyst stage. RHAMM/IHABP mRNA abundance was significantly (P < 0.05) lower in embryos recovered in serum-containing medium than in embryos from serum-free media. Immunohistochemistry revealed the presence of RHAMM/IHABP first in 8-cell stages. Whereas RHAMM staining in 8-cell and morula stages was intense, it was weaker in blastocysts. Embryonic secretion of HA increased from the 2-cell stage until the 8-cell stage and then decreased in 16-cell embryos. After this, HA secretion increased in expanded and hatched blastocyst stages. These data suggest that the positive effects of HA on in vitro-produced bovine embryos may be mediated at least in part by RHAMM/IHABP.

Interactions of the extracellular matrix component hyaluronic acid and its cellular receptors CD44 and RHAMM/IHABP have been linked to tumor progression and metastasis formation. We investigated the expression and hyaluronic-acid-dependent functions of CD44 and RHAMM/IHABP in human melanoma. Immunohistochemistry of tumor specimens at different stages of melanoma progression revealed an increased expression of CD44 and RHAMM/IHABP. High mRNA expression of CD44 was found in three highly tumorigenic melanoma cell lines compared with less tumorigenic melanoma cells or nontransformed melanocytes. RHAMM/IHABP expression was upregulated in all cell lines analyzed but not in melanocytes. In contrast to the cell surface localization of CD44, RHAMM/IHABP was detected exclusively within the cytoplasm of melanoma cells. Binding and adhesion of melanoma cells to hyaluronic acid is mainly CD44 dependent as it was inhibited to 60%--80% by an anti-CD44 monoclonal antibody whereas anti-RHAMM/IHABP sera had no effect. Culture of melanoma cells in the presence of hyaluronic acid resulted in a dose-dependent, CD44-mediated increase of melanoma cell proliferation and enhanced release of basic fibroblast growth factor and transforming growth factor beta 1. We conclude that (i) the expression of CD44 and RHAMM/IHABP is increased during melanoma progression, (ii) CD44 is the principal hyaluronic acid surface receptor on melanoma cells, and (iii) the hyaluronic-acid-induced increase of the proliferative capacity of melanoma cells is mainly dependent on CD44--hyaluronic acid interactions.

Folding and assembly of polypeptides translocated into the rough endoplasmic reticulum (RER) is facilitated by a set of resident proteins in the lumen of the RER. We studied the regulation of synthesis of the RER luminal proteins immunoglobulin heavy chain binding protein (BiP) and protein disulfide isomerase (PDI), and of the cytosolic stress 70 protein (hsc70) after hormonal stimulation of the pancreatic exocrine secretory pathway. Their rate of synthesis was assessed at both mRNA and protein levels and under two experimental conditions that are associated with large increases in exocrine production. After in vivo stimulation of the pancreas by either endogenous release of cholecystokinin (CCK) following proteinase inhibitor feeding (FOY-305) or by in vivo infusion of the pancreatic secretagogue cerulein, the relative rates of synthesis detected for BiP and PDI were enhanced 2.5 to 4-fold compared to control. Interestingly, the kinetics and the degree of hsc70 mRNA induction were almost identical to those of BiP and PDI, suggesting coordinated hormonal regulation of BiP, PDI as hormonal stimulation was even twice that following heat shock treatment. The mRNA levels of calreticulin (CaBP3) increased up to 2.3-fold with a kinetic comparable to that of BiP, PDI and hsc 70, while CaBP1 and the RER membrane proteins, ribophorin I and the signal recognition particle receptor did not show any changes in their relative mRNA amounts after hormonal stimulation. The increase in the rates of PDI and chaperone biosynthesis exceeds the associated increase in total protein biosynthesis. In vitro experiments, using transformed rat acinar cells (AR4-2J) in which pancreatic enzyme synthesis can be induced by glycocorticoid hormones, demonstrated that induction of PDI and chaperone mRNA synthesis preceded extensive mRNA expression of secretory proteins.