947 resultados para Cancer systems biology
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BACKGROUND Breast cancer (BC) is the most commonly diagnosed cancer and a leading cause of death in younger women. METHODS We analysed incidence, mortality and relative survival (RS) in women with BC aged 20-49 years at diagnosis, between 1996 and 2009 in Switzerland. Trends are reported as estimated annual percentage changes (EAPC). RESULTS Our findings confirm a slight increase in the incidence of BC in younger Swiss women during the period 1996-2009. The increase was largest in women aged 20-39 years (EAPC 1.8%). Mortality decreased in both age groups with similar EAPCs. Survival was lowest among women 20-39 years (10-year RS 73.4%). We observed no notable differences in stage of disease at diagnosis that might explain these differences. CONCLUSIONS The increased incidence and lower survival in younger women diagnosed with BC in Switzerland indicates possible differences in risk factors, tumour biology and treatment characteristics that require additional examination.
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UNLABELLED Ex vivo studies have shown that the gastrin releasing peptide receptor (GRPr) is overexpressed on almost all primary prostate cancers, making it a promising target for prostate cancer imaging and targeted radiotherapy. METHODS Biodistribution, dosimetry and tumor uptake of the GRPr antagonist ⁶⁴Cu-CB-TE2A-AR06 [(⁶⁴Cu-4,11-bis(carboxymethyl)-1,4,8,11-tetraazabicyclo(6.6.2)hexadecane)-PEG₄-D-Phe-Gln-Trp-Ala-Val-Gly-His-Sta-LeuNH₂] were studied by PET/CT in four patients with newly diagnosed prostate cancer (T1c-T2b, Gleason 6-7). RESULTS No adverse events were observed after injection of ⁶⁴Cu-CB-TE2A-AR06. Three of four tumors were visualized with high contrast [tumor-to-prostate ratio > 4 at 4 hours (h) post injection (p.i.)], one small tumor (T1c, < 5% tumor on biopsy specimens) showed moderate contrast (tumor-to-prostate ratio at 4 h: 1.9). Radioactivity was cleared by the kidneys and only the pancreas demonstrated significant accumulation of radioactivity, which rapidly decreased over time. CONCLUSION ⁶⁴Cu-CB-TE2A-AR06 shows very favorable characteristics for imaging prostate cancer. Future studies evaluating ⁶⁴Cu-CB-TE2A-AR06 PET/CT for prostate cancer detection, staging, active surveillance, and radiation treatment planning are necessary.
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BACKGROUND: The understanding of molecular mechanisms leading to poor prognosis in pancreatic cancer may help develop treatment options. N-myc downstream-regulated gene-1 (NDRG1) has been correlated to better prognosis in pancreatic cancer. Therefore, we thought to analyze how the loss of NDRG1 affects progression in an orthotopic xenograft animal model of recurrence. METHODS: Capan-1 cells were silenced for NDRG1 (C(sil)) or transfected with scrambled shRNA (C(scr)) and compared for anchorage-dependent and anchorage-independent growth, invasion and tube formation in vitro. In an orthotopic xenograft model of recurrence tumors were grown in the pancreatic tail. The effect of NDRG1 silencing was evaluated on tumor size and metastasis. RESULTS: The silencing of NDRG1 in Capan-1 cells leads to more aggressive tumor growth and metastasis. We found faster cell growth, double count of invaded cells and 1.8-fold increase in tube formation in vitro. In vivo local tumors were 5.9-fold larger (p = 0.006) and the number of metastases was higher in animals with tumors silenced for NDRG1 primarily (3 vs. 1.1; p = 0.005) and at recurrence (3.3 vs. 0.9; p = 0.015). CONCLUSION: NDRG1 may be an interesting therapeutic target as its silencing in human pancreatic cancer cells leads to a phenotype with more aggressive tumor growth and metastasis.
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In aerobic eukaryotic cells, the high energy metabolite ATP is generated mainly within the mitochondria following the process of oxidative phosphorylation. The mitochondrial ATP is exported to the cytoplasm using a specialized transport protein, the ADP/ATP carrier, to provide energy to the cell. Any deficiency or dysfunction of this membrane protein leads to serious consequences on cell metabolism and can cause various diseases such as muscular dystrophy. Described as a decisive player in the programmed cell death, it was recently shown to play a role in cancer. The objective of this review is to summarize the current knowledge of the involvement of the ADP/ATP carrier, encoded by the SLC25A4, SLC25A5, SLC25A6 and SLC25A31 genes, in human diseases and of the efforts made at designing different model systems to study this carrier and the associated pathologies through biochemical, genetic, and structural approaches.
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Various corphinoid model systems bearing a methyl group at the position C-20 have been found to undergo regioselective chemical -methylation at the ligand periphery, mimicking enzymic -methylation occurring in vitamin-B biosynthesis.
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Engineered nanomaterials have unique and novel properties enabling wide-ranging new applications in nearly all fields of research. As these new properties have raised concerns about potential adverse effects for the environment and human health, extensive efforts are underway to define reliable, cost- and time-effective, as well as mechanistic-based testing strategies to replace the current method of animal testing, which is still the most prevalent model used for the risk assessment of chemicals. Current approaches for nanomaterials follow this line. The aim of this review is to explore and qualify the relevance of new in vitro and ex vivo models in (nano)material safety assessment, a crucial prerequisite for translation into applications.
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Several (pre-) clinical trials are currently investigating the benefit of HER2-targeted therapy in urothelial bladder cancer (UBC). Patients with HER2 amplified UBC could potentially profit from these therapies. However, little is known about histomorphology, HER2 protein expression patterns and occurrence of alterations in the HER2 gene in their tumors. Among 150 metastasizing primary UBC, 13 HER2 amplified tumors were identified. Their histopathological features were compared with 13 matched, non-amplified UBC. HER2 protein expression was determined by immunohistochemistry. The 26 tumors were screened for mutations in exons 19 and 20 of the HER2 gene. UBC with HER2 amplification presented with a broad variety of histological variants (median 2 vs. 1), frequently featured micropapillary tumor components (77 % vs. 8 %) and demonstrated a high amount of tumor associated inflammation. Immunohistochemically, 10 of 13 (77 %) HER2 amplified tumors were strongly HER2 protein positive. Three tumors (23 %) were scored as HER2 negative. One of the HER2 amplified tumors harbored a D769N mutation in exon 19 of the HER2 gene; all other tested tumors were wild type. In conclusion, HER2 amplified UBC feature specific morphological characteristics. They frequently express the HER2 protein diffusely and are, therefore, promising candidates for HER2 targeted therapies. The detection of mutations at the HER2 locus might add new aspects to molecular testing of UBC.
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Tumor budding (single tumor cells or small tumor cell clusters) at the invasion front of colorectal cancer (CRC) is an adverse prognostic indicator linked to epithelial-mesenchymal transition. This study characterized the immunogenicity of tumor buds by analyzing the expression of the major histocompatibility complex (MHC) class I in the invasive tumor cell compartment. We hypothesized that maintenance of a functional MHC-I antigen presentation pathway, activation of CD8+ T-cells, and release of antitumoral effector molecules such as cytotoxic granule-associated RNA binding protein (TIA1) in the tumor microenvironment can counter tumor budding and favor prolonged patient outcome. Therefore, a well-characterized multipunch tissue microarray of 220 CRCs was profiled for MHC-I, CD8, and TIA1 by immunohistochemistry. Topographic expression analysis of MHC-I was performed using whole tissue sections (n = 100). Kirsten rat sarcoma viral oncogene homolog (KRAS) and B-Raf proto-oncogene, serine/threonine kinase (BRAF) mutations, mismatch repair (MMR) protein expression, and CpG-island methylator phenotype (CIMP) were investigated. Our results demonstrated that membranous MHC-I expression is frequently down-regulated in the process of invasion. Maintained MHC-I at the invasion front strongly predicted low-grade tumor budding (P = 0.0004). Triple-positive MHC-I/CD8/TIA1 in the tumor microenvironment predicted early T-stage (P = 0.0031), absence of lymph node metastasis (P = 0.0348), lymphatic (P = 0.0119) and venous invasion (P = 0.006), and highly favorable 5-year survival (90.9% vs 39.3% in triple-negative patients; P = 0.0032). MHC-I loss was frequent in KRAS-mutated, CD8+ CRC (P = 0.0228). No relationship was observed with CIMP, MMR, or BRAF mutation. In conclusion, tumor buds may evade immune recognition through downregulation of membranous MHC-I. A combined profile of MHC-I/CD8/TIA1 improves the prognostic value of antitumoral effector cells and should be preferred to a single marker approach.
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Tumor budding in colorectal cancer (CRC) is recognized as a valuable prognostic factor but its translation into daily histopathology practice has been delayed by lack of agreement on the optimal method of assessment. Within the context of the Swiss Association of Gastrointestinal Pathology (SAGIP), we performed a multicenter interobserver study on tumor budding, comparing hematoxylin and eosin (H&E) with pan-cytokeratin staining using a 10 high power field (10HPF) and hotspot (1HPF) method. Two serial sections of 50 TNM stage II-IV surgically treated CRC were stained for H&E and pan-cytokeratin. Tumor buds were scored by independent observers at six participating centers in Switzerland and Austria using the 10HPF and 1HPF method on a digital pathology platform. Pearson correlation (r) and intra-class correlation coefficients (ICC) comparing scores between centers were calculated. Three to four times more tumor buds were detected in pan-cytokeratin compared to H&E slides. Correlation coefficients for tumor budding counts between centers ranged from r = 0.46 to r = 0.91 for H&E and from r = 0.73 to r = 0.95 for pan-cytokeratin slides. Interobserver agreement across all centers was excellent for pan-cytokeratin [10HPF: ICC = 0.83 and 1HPF: ICC = 0.8]. In contrast, assessment of tumor budding on H&E slides reached only moderate agreement [10HPF: ICC = 0.58 and 1HPF: ICC = 0.49]. Based on previous literature and our findings, we recommend (1) pan-cytokeratin staining whenever possible, (2) 10HPF method for resection specimens, and (3) 1HPF method for limited material (preoperative biopsy or pT1). Since tumor budding counts can be used to determine probabilities of relevant outcomes and as such more optimally complement clinical decision making, we advocate the avoidance of cutoff scores.
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Tumor budding refers to single or small cluster of tumor cells detached from the main tumor mass. In colon cancer high tumor budding is associated with positive lymph nodes and worse prognosis. Therefore, we investigated the value of tumor budding as a predictive feature of lymph node status in breast cancer (BC). Whole tissue sections from 148 surgical resection specimens (SRS) and 99 matched preoperative core biopsies (CB) with invasive BC of no special type were analyzed on one slide stained with pan-cytokeratin. In SRS, the total number of intratumoral (ITB) and peripheral tumor buds (PTB) in ten high-power fields (HPF) were counted. A bud was defined as a single tumor cell or a cluster of up to five tumor cells. High tumor budding equated to scores averaging >4 tumor buds across 10HPFs. In CB high tumor budding was defined as ≥10 buds/HPF. The results were correlated with pathological parameters. In SRS high PTB stratified BC with lymph node metastases (p ≤ 0.03) and lymphatic invasion (p ≤ 0.015). In CB high tumor budding was significantly (p = 0.0063) associated with venous invasion. Pathologists are able, based on morphology, to categorize BC into a high and low risk groups based in part on lymph node status. This risk assessment can be easily performed during routine diagnostics and it is time and cost effective. These results suggest that high PTB is associated with loco-regional metastasis, highlighting the possibility that this tumor feature may help in therapeutic decision-making.
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BACKGROUND Metastasis of colorectal cancer (CRC) is directly linked to patient survival. We previously identified the novel gene Metastasis Associated in Colon Cancer 1 (MACC1) in CRC and demonstrated its importance as metastasis inducer and prognostic biomarker. Here, we investigate the geographic expression pattern of MACC1 in colorectal adenocarcinoma and tumor buds in correlation with clinicopathological and molecular features for improvement of survival prognosis. METHODS We performed geographic MACC1 expression analysis in tumor center, invasive front and tumor buds on whole tissue sections of 187 well-characterized CRCs by immunohistochemistry. MACC1 expression in each geographic zone was analyzed with Mismatch repair (MMR)-status, BRAF/KRAS-mutations and CpG-island methylation. RESULTS MACC1 was significantly overexpressed in tumor tissue as compared to normal mucosa (p < 0.001). Within colorectal adenocarcinomas, a significant increase of MACC1 from tumor center to front (p = 0.0012) was detected. MACC1 was highly overexpressed in 55% tumor budding cells. Independent of geographic location, MACC1 predicted advanced pT and pN-stages, high grade tumor budding, venous and lymphatic invasion (p < 0.05). High MACC1 expression at the invasive front was decisive for prediction of metastasis (p = 0.0223) and poor survival (p = 0.0217). The geographic pattern of MACC1 did not correlate with MMR-status, BRAF/KRAS-mutations or CpG-island methylation. CONCLUSION MACC1 is differentially expressed in CRC. At the invasive front, MACC1 expression predicts best aggressive clinicopathological features, tumor budding, metastasis formation and poor survival outcome.
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BACKGROUND There is evidence that tumour-stroma interactions have a major role in the neoplastic progression of pancreatic ductal adenocarcinoma (PDAC). Tumour budding is thought to reflect the process of epithelial-mesenchymal transition (EMT); however, the relationship between tumour buds and EMT remains unclear. Here we characterize the tumour-budding- and stromal cells in PDAC at protein and mRNA levels concerning factors involved in EMT. METHODS mRNA in situ hybridisation and immunostaining for E-cadherin, β-catenin, SNAIL1, ZEB1, ZEB2, N-cadherin and TWIST1 were assessed in the main tumour, tumour buds and tumour stroma on multipunch tissue microarrays from 120 well-characterised PDACs and associated with the clinicopathological features, including peritumoural (PTB) and intratumoural (ITB) budding. RESULTS Tumour-budding cells showed increased levels of ZEB1 (P<0.0001) and ZEB2 (P=0.0119) and reduced E-cadherin and β-catenin (P<0.0001, each) compared with the main tumour. Loss of membranous β-catenin in the main tumour (P=0.0009) and tumour buds (P=0.0053), without nuclear translocation, as well as increased SNAIL1 in tumour and stromal cells (P=0.0002, each) correlated with high PTB. ZEB1 overexpression in the main tumour-budding and stromal cells was associated with high ITB (P=0.0084; 0.0250 and 0.0029, respectively) and high PTB (P=0.0005; 0.0392 and 0.0007, respectively). ZEB2 overexpression in stromal cells correlated with higher pT stage (P=0.03), lymphatic invasion (P=0.0172) and lymph node metastasis (P=0.0152). CONCLUSIONS In the tumour microenvironment of phenotypically aggressive PDAC, tumour-budding cells express EMT hallmarks at protein and mRNA levels underlining their EMT-type character and are surrounded by stromal cells expressing high levels of the E-cadherin repressors ZEB1, ZEB2 and SNAIL1, this being strongly associated with the tumour-budding phenotype. Moreover, our findings suggest the existence of subtypes of stromal cells in PDAC with phenotypical and functional heterogeneity.
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Spider-phobic individuals are characterized by exaggerated expectancies to be faced with spiders (so-called encounter expectancy bias). Whereas phobic responses have been linked to brain systems mediating fear, little is known about how the recruitment of these systems relates to exaggerated expectancies of threat. We used fMRI to examine spider-phobic and control participants while they imagined visiting different locations in a forest after having received background information about the likelihood of encountering different animals (spiders, snakes, and birds) at these locations. Critically, imagined encounter expectancies modulated brain responses differently in phobics as compared with controls. Phobics displayed stronger negative modulation of activity in the lateral prefrontal cortex, precuneus, and visual cortex by encounter expectancies for spiders, relative to snakes or birds (within-participants analysis); these effects were not seen in controls. Between-participants correlation analyses within the phobic group further corroborated the hypothesis that these phobia-specific modulations may underlie irrationality in encounter expectancies (deviations of encounter expectancies from objective background information) in spider phobia; the greater the negative modulation a phobic participant displayed in the lateral prefrontal cortex, precuneus, and visual cortex, the stronger was her bias in encounter expectancies for spiders. Interestingly, irrationality in expectancies reflected in frontal areas relied on right rather than left hemispheric deactivations. Our data accord with the idea that expectancy biases in spider phobia may reflect deficiencies in cognitive control and contextual integration that are mediated by right frontal and parietal areas.