Pancreatic ductal adenocarcinoma (PDAC) is an inherently chemoresistant tumor. Chemotherapy leads to apoptosis of cancer cells, and in previous studies we have shown that tumor-associated macrophage (TAM) infiltration increases following chemotherapy in PDAC. Since one of the main functions of macrophages is to eliminate apoptotic cells, we hypothesized that TAMs phagocytose chemotherapy-induced apoptotic cells and secrete factors, which favor PDAC chemoresistance.
View Article and Find Full Text PDFBackground: Given our preclinical data showing synergy between dovitinib and paclitaxel in preclinical models we conducted this phase I trial aiming to define the recommended phase II-dose (RP2D) on the basis of toxicity and pharmacodynamic criteria while searching for genetic variants that could sensitize patients to the regimen under study.
Patients And Methods: A 3+3 escalation schedule was adopted. Seriated FGF23 and dovitinib and paclitaxel pharmacokinetic profiles were determined along a single-agent dovitinib "priming-phase" followed by a dovitinib + paclitaxel combination phase.
Cisplatin is commonly used in cancer therapy and yeast cells are also sensitive to this compound. We present a transcriptome analysis discriminating between RNA changes induced by cisplatin treatment, which are dependent on or independent of SKY1 function--a gene whose deletion increases resistance to the drug. Gene expression changes produced by addition of cisplatin to W303 and W303-Δsky1 cells were recorded using DNA microarrays.
View Article and Find Full Text PDFNK/T-cell lymphoma (NKTCL) is the most frequent EBV-related NK/T-cell disease. Its clinical manifestations overlap with those of familial haemophagocytic lymphohistiocytosis (FHLH). Since PERFORIN (PRF1) mutations are present in FHLH, we analysed its role in a series of 12 nasal and 12 extranasal-NKTCLs.
View Article and Find Full Text PDFThe JAK2V617F allele burden has been identified as a risk factor for vascular events and myelofibrotic transformation in polycythemia vera (PV) and essential thrombocythemia (ET). However, all previous studies have evaluated a single time point JAK2V617F measurement. Therefore, the frequency and the clinical significance of changes in the JAK2V617F mutant load occurring during the disease evolution remain unknown.
View Article and Find Full Text PDFPeripheral T-cell lymphomas are very aggressive hematologic malignancies for which there is no targeted therapy. New, rational approaches are necessary to improve the very poor outcome in these patients. Phosphatidylinositol-3-kinase is one of the most important pathways in cell survival and proliferation.
View Article and Find Full Text PDFBackground And Objectives: Our study has investigated the presence of the mutation V617F in the JAK2 gene in patients diagnosed with chronic myeloproliferative neoplasms (MPNs). Furthermore, we determined if JAK2 (V617F) allelic burden associates with a specific clinical phenotype and if its quantification can be used as a marker to predict outcome and complications in patients with MPNs.
Patients And Methods: A retrospective observational study was conducted from 1987 to 2011 in the Haematology Department of La Paz University Hospital.
Vitamin D deficiency is associated with the high risk of colon cancer and a variety of other diseases. The active vitamin D metabolite 1α,25-dihydroxyvitamin D(3) (1,25(OH)(2)D(3)) regulates gene transcription via its nuclear receptor (VDR), and posttranscriptional regulatory mechanisms of gene expression have also been proposed. We have identified microRNA-22 (miR-22) and several other miRNA species as 1,25(OH)(2)D(3) targets in human colon cancer cells.
View Article and Find Full Text PDFCell competition promotes the elimination of weaker cells from a growing population. Here we investigate how cells of Drosophila wing imaginal discs distinguish "winners" from "losers" during cell competition. Using genomic and functional assays, we have identified several factors implicated in the process, including Flower (Fwe), a cell membrane protein conserved in multicellular animals.
View Article and Find Full Text PDFBackground: Cells have the ability to respond and adapt to environmental changes through activation of stress-activated protein kinases (SAPKs). Although p38 SAPK signalling is known to participate in the regulation of gene expression little is known on the molecular mechanisms used by this SAPK to regulate stress-responsive genes and the overall set of genes regulated by p38 in response to different stimuli.
Results: Here, we report a whole genome expression analyses on mouse embryonic fibroblasts (MEFs) treated with three different p38 SAPK activating-stimuli, namely osmostress, the cytokine TNFalpha and the protein synthesis inhibitor anisomycin.
Purpose: The mechanisms involved in the appearance of a second neoplasia in patients with Hodgkin's disease (HD) are probably related to the genomic damage induced by the treatments administered and its repair. Here, we searched for some constitutive molecular mechanisms that in a basal manner may influence the behavior of HD patients.
Experimental Design: We aimed to evaluate with the Comet Assay whether baseline, induced, and unrepaired DNA damage differ between HD patients who did not develop a second neoplasia (HD-NST), HD patients who developed a second tumor (HD-ST), and healthy individuals; and to identify, through cDNA microarray hybridization, an expression signature of genes that could discriminate between the three groups.
HEp-2 cells that survived a lytic infection with Human Respiratory Syncytial Virus (HRSV) were grown to obtain a persistently infected culture that produced relatively high amounts of virus (10(6)-10(7) pfu/ml) for more than twenty passages. The cells in this culture were heterogeneous with regard to the expression of viral antigens, ranging from high to undetectable levels. However, all cell clones derived from the persistent culture did not produce infectious virus or viral antigens and grew more slowly than the original uninfected HEp-2 cells.
View Article and Find Full Text PDFTo investigate cellular factors involved in HIV-1 chronic infection, three cell lines chronically infected with the same HIV-1 viral isolate (s61) were studied by cDNA microarray analysis. Two T cell lines, H61 and M61, showed the characteristics of a persistent infection whereas U61 cell line displayed a latent infection pattern. Analysis of genes with altered expression in the three cell lines revealed evidence of apoptosis control by up-regulation of anti-apoptotic genes and down-regulation of pro-apoptotic genes.
View Article and Find Full Text PDFBackground: The blood of cancer patients is known to contain fragments of RNA released from the tumor. The application of genomic profiling techniques to plasma RNA may allow the unbiased selection of cancer markers in the blood, but the informative value of genomic profiling of plasma RNA is currently unknown.
Methods: We used cDNA microarray hybridization to perform genomic profiling of plasma RNA from colorectal cancer (CRC) patients and from healthy donors.
cDNA microarray technology was applied to time course analysis of differentially expressed genes in A549 cells following human respiratory syncytial virus (HRSV) infection. Both up- and down-regulation of cellular genes were observed in a time-dependent manner. However, gene up-regulation prevailed over gene down-regulation.
View Article and Find Full Text PDFMultiple factors are involved in the translation of functional genomic results into proteins for proteome research and target validation on tumoral tissues. In this report, genes were selected by using DNA microarrays on a panel of colorectal cancer (CRC) paired samples. A large number of up-regulated genes in colorectal cancer patients were investigated for cellular location, and those corresponding to membrane or extracellular proteins were used for a non-biased expression in Escherichia coli.
View Article and Find Full Text PDFThe identification of specific protein markers for colorectal cancer would provide the basis for early diagnosis and detection, as well as clues for understanding the molecular mechanisms governing cancer progression. In this report, we describe the proteomic analysis of the samples of colorectal cancer corresponding to seven patients. We have used the highly sensitive two-dimensional differential gel electrophoresis (2-D DIGE) coupled with mass spectrometry (MS) for the identification of proteins differentially expressed in tumoral and neighboring normal mucosa.
View Article and Find Full Text PDFPurpose: T-Cell lymphomas constitute heterogeneous and aggressive tumors in which pathogenic alterations remain largely unknown. Expression profiling has demonstrated to be a useful tool for molecular classification of tumors.
Experimental Design: Using DNA microarrays (CNIO-OncoChip) containing 6386 cancer-related genes, we established the expression profiling of T-cell lymphomas and compared them to normal lymphocytes and lymph nodes.
LKB1, a tumor-suppressor gene that codifies for a serine/threonine kinase, is mutated in the germ-line of patients affected with the Peutz-Jeghers syndrome (PJS), which have an increased incidence of several cancers including gastrointestinal, pancreatic and lung carcinomas. Regarding tumors arising in non-PJS patients, we recently observed that at least one-third of lung adenocarcinomas (LADs) harbor somatic LKB1 gene mutations, supporting a role for LKB1 in the origin of some sporadic tumors. To characterize the pattern of LKB1 mutations in LADs further, we first screened for LKB1 gene alterations (gene mutations, promoter hypermethylation and homozygous deletions) in 19 LADs and, in agreement with our previous data, five of them (26%) were shown to harbor mutations, all of which gave rise to a truncated protein.
View Article and Find Full Text PDFInterferon-alpha therapy has been shown to be active in the treatment of mycosis fungoides although the individual response to this therapy is unpredictable and dependent on essentially unknown factors. In an effort to better understand the molecular mechanisms of interferon-alpha resistance we have developed an interferon-alpha resistant variant from a sensitive cutaneous T-cell lymphoma cell line. We have performed expression analysis to detect genes differentially expressed between both variants using a cDNA microarray including 6386 cancer-implicated genes.
View Article and Find Full Text PDFGenome-wide studies have recently revealed the unexpected complexity of the genetic response to apparently simple physiological changes. Here, we show that when yeast cells are exposed to Cd(2+), most of the sulfur assimilated by the cells is converted into glutathione, a thiol-metabolite essential for detoxification. Cells adapt to this vital metabolite requirement by modifying globally their proteome to reduce the production of abundant sulfur-rich proteins.
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