213 research outputs found
The Collins-Roscoe mechanism and D-spaces
We prove that if a space X is well ordered , or linearly
semi-stratifiable, or elastic then X is a D-space
Conditional inactivation of the Men1 gene leads to pancreatic and pituitary tumorigenesis but does not affect normal development of these tissues
Mutations of the MEN1 gene, encoding the tumor suppressor menin, predispose individuals to the cancer syndrome multiple endocrine neoplasia type 1, characterized by the development of tumors of the endocrine pancreas and anterior pituitary and parathyroid glands. We have targeted the murine Men1 gene by using Cre recombinase-loxP technology to develop both total and tissue-specific knockouts of the gene. Conditional homozygous inactivation of the Men1 gene in the pituitary gland and endocrine pancreas bypasses the embryonic lethality associated with a constitutional Men1(-/-) genotype and leads to beta-cell hyperplasia in less than 4 months and insulinomas and prolactinomas starting at 9 months. The pituitary gland and pancreas develop normally in the conditional absence of menin, but loss of this transcriptional cofactor is sufficient to cause beta-cell hyperplasia in some islets; however, such loss is not sufficient to initiate pituitary gland tumorigenesis, suggesting that additional genetic events are necessary for the latter
Baseline neutrophil-lymphocyte ratio holds no prognostic value for esophageal and junctional adenocarcinoma in patients treated with neoadjuvant chemotherapy
BACKGROUND: Several studies have reported that neutrophil-lymphocyte ratio (NLR) can predict survival in esophageal and gastroesophageal junction adenocarcinoma, as it reflects systemic inflammation. Hence, we aimed to determine whether baseline NLR holds prognostic value for esophageal adenocarcinoma patients treated with neoadjuvant chemotherapy (nCT) followed by surgery. METHODS: We studied the data of 139 patients that received nCT before undergoing esophagectomy with curative intent, all identified from a prospectively maintained database (1998-2016). Pretreatment hematology reports were used to calculate the baseline NLR. A receiver operating characteristic curve (ROC-curve) was plotted to determine an optimal cutoff value. NLR quartiles were used to display possible differences between groups in relation to overall survival (OS) and disease-free survival (DFS) using the method of Kaplan-Meier. Cox regression analysis was performed to assess the prognostic value of NLR. RESULTS: The median OS and DFS times were 46 months (interquartile range [IQR]: 19-166) and 30 months (IQR: 13-166], respectively, for the entire cohort. The ROC-curve showed that NLR has no discriminating power for survival status (area under the curve = 0.462) and therefore no optimal cutoff value could be determined. There were no statistically significant differences in median OS times for NLR quartiles: 65 (Q1), 32 (Q2), 45 (Q3), and 46 months (Q4) (P = 0.926). Similarly, DFS showed no difference between quartile groups, with median survival times of 27 (Q1), 19 (Q2), 36 (Q3), and 20 months (Q4) (P = 0.973). Age, pN, pM, and resection margin were independent prognostic factors for both OS and DFS. On the contrary, NLR was not associated with OS or DFS in univariable and multivariable analyses. CONCLUSION: Baseline NLR holds no prognostic value for esophageal and gastroesophageal junction adenocarcinoma patients treated with nCT in this study, in contrast to other recently published papers. This result questions the validity of NLR as a reliable prognostic indicator and its clinical usefulness in these patients
The well-ordered (F) spaces are D-spaces
We studied the relationships between Collins-Roscoe mechanism and D-spaces,
proved that well-ordered (F) spaces are D-spaces. This positively answered a
question asked by D.Soukup and Y.Xu before.Comment: 6 page
A common intronic variant of PARP1 confers melanoma risk and mediates melanocyte growth via regulation of MITF
Previous genome-wide association studies have identified a melanoma-associated locus at 1q42.1 that encompasses a ~100-kb region spanning the PARP1 gene. Expression quantitative trait locus (eQTL) analysis in multiple cell types of the melanocytic lineage consistently demonstrated that the 1q42.1 melanoma risk allele (rs3219090[G]) is correlated with higher PARP1 levels. In silico fine-mapping and functional validation identified a common intronic indel, rs144361550 (−/GGGCCC; r2 = 0.947 with rs3219090), as displaying allele-specific transcriptional activity. A proteomic screen identified RECQL as binding to rs144361550 in an allele-preferential manner. In human primary melanocytes, PARP1 promoted cell proliferation and rescued BRAFV600E-induced senescence phenotypes in a PARylation-independent manner. PARP1 also transformed TERT-immortalized melanocytes expressing BRAFV600E. PARP1-mediated senescence rescue was accompanied by transcriptional activation of the melanocyte-lineage survival oncogene MITF, highlighting a new role for PARP1 in melanomagenesis
The role of 5-hydroxytryptamine receptor subtypes in the regulation of brain-derived neurotrophic factor gene expression
Complex structural rearrangements are present in high-grade dysplastic Barrett\u27s oesophagus samples
Background: Oesophageal adenocarcinoma (EAC) incidence is increasing and has a poor survival rate. Barrett’s oesophagus (BE) is a precursor condition that is associated with EAC and often occurs in conjunction with chronic gastro-oesophageal reflux, however many individuals diagnosed with BE never progress to cancer. An understanding of the genomic features of BE and EAC may help with the early identification of at-risk individuals.
Methods: In this study, we assessed the genomic features of 16 BE samples using whole-genome sequencing. These included non-dysplastic samples collected at two time-points from two BE patients who had not progressed to EAC over several years. Seven other non-dysplastic samples and five dysplastic BE samples with high-grade dysplasia were also examined. We compared the genome profiles of these 16 BE samples with 22 EAC samples.
Results: We observed that samples from the two non-progressor individuals had low numbers of somatic single nucleotide variants, indels and structural variation events compared to dysplastic and the remaining non-dysplastic BE. EAC had the highest level of somatic genomic variations. Mutational signature 17, which is common in EAC, was also present in non-dysplastic and dysplastic BE, but was not present in the non-progressors. Many dysplastic samples had mutations in genes previously reported in EAC, whereas only mutations in CDKN2A or in the fragile site genes appeared common in non-dysplastic samples. Rearrangement signatures were used to identify a signature associated with localised complex events such as chromothripsis and breakage fusion-bridge that are characteristic of EACs. Two dysplastic BE samples had a high contribution of this signature and contained evidence of localised rearrangements. Two other dysplastic samples also had regions of localised structural rearrangements. There was no evidence for complex events in non-dysplastic samples.
Conclusions: The presence of complex localised rearrangements in dysplastic samples indicates a need for further investigations into the role such events play in the progression from BE to EAC
Use of plant stanol ester margarine among persons with and without cardiovascular disease: Early phases of the adoption of a functional food in Finland
Genetic variants in FGFR2 and FGFR4 genes and skin cancer risk in the Nurses' Health Study
<p>Abstract</p> <p>Background</p> <p>The human fibroblast growth factor (FGF) and its receptor (FGFR) play an important role in tumorigenesis. Deregulation of the <it>FGFR2 </it>gene has been identified in a number of cancer sites. Overexpression of the <it>FGFR4 </it>protein has been linked to cutaneous melanoma progression. Previous studies reported associations between genetic variants in the <it>FGFR2 </it>and <it>FGFR4 </it>genes and development of various cancers.</p> <p>Methods</p> <p>We evaluated the associations of four genetic variants in the <it>FGFR2 </it>gene highly related to breast cancer risk and the three common tag-SNPs in the <it>FGFR4 </it>gene with skin cancer risk in a nested case-control study of Caucasians within the Nurses' Health Study (NHS) among 218 melanoma cases, 285 squamous cell carcinoma (SCC) cases, 300 basal cell carcinoma (BCC) cases, and 870 controls.</p> <p>Results</p> <p>We found no evidence for associations between these seven genetic variants and the risks of melanoma and nonmelanocytic skin cancer.</p> <p>Conclusion</p> <p>Given the power of this study, we did not detect any contribution of genetic variants in the <it>FGFR2 </it>or <it>FGFR4 </it>genes to inherited predisposition to skin cancer among Caucasian women.</p
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