Search results for "Intestin"
showing 10 items of 2215 documents
Homozygous mutations in exon 11 of c-KIT in GIST define a group of high risk patients
2010
Gastrointestinal stromal tumors are the most common mesenchymal neoplasms of the gastrointestinal tract. Gain of function mutations of tyrosine kinase receptors, c-KIT, and PDGFRa have been identified in most GIST; c-KIT exon 11 mutations are the most common. The type of c-KIT or PDGFRa mutation indicates tumor responsiveness to imatinib treatment or progression, although GIST with homozygous mutation has been poorly studied. We analyzed 145 GIST at the immunohistopathologic and genetic levels. Formalin-fixed, paraffin-embedded sections were used for our studies. The histological variables included: mitotic count per 50 HPF, necrosis, pleomorphism, and cell type. The immunophenotype was def…
Uncommon Synchronous Association between Ovarian Carcinoma and Gastrointestinal Stromal Tumor: A Case Study and Literature Review
2013
Background The association of gastrointestinal stromal tumors (GIST) and other cancers is well known, but its synchronous occurrence with gynecological malignancies is very uncommon. Usually, the diagnosis is accidentally established. We describe a patient with GIST and concurrent ovarian cancer and discuss the clinical implications of this finding. Case report A 64-year-old woman with a prior diagnosis of ovarian cancer developed a second recurrence after having undergone two operations and adjuvant chemotherapy. While tumor debulking was performed, a small, nonsuspicious lesion was removed from the greater curvature of the stomach. Histology revealed a GIST. Conclusion The association of …
Mast Cells Infiltrating Inflamed or Transformed Gut Alternatively Sustain Mucosal Healing or Tumor Growth.
2015
Abstract Mast cells (MC) are immune cells located next to the intestinal epithelium with regulatory function in maintaining the homeostasis of the mucosal barrier. We have investigated MC activities in colon inflammation and cancer in mice either wild-type (WT) or MC-deficient (KitW-sh) reconstituted or not with bone marrow-derived MCs. Colitis was chemically induced with dextran sodium sulfate (DSS). Tumors were induced by administering azoxymethane (AOM) intraperitoneally before DSS. Following DSS withdrawal, KitW-sh mice showed reduced weight gain and impaired tissue repair compared with their WT littermates or KitW-sh mice reconstituted with bone marrow-derived MCs. MCs were localized i…
Metabolic Imaging in Microregions of Tumors and Normal Tissues With Bioluminescence and Photon Counting
1988
A method has been developed for metabolic imaging on a microscopic level in tumors, tumor spheroids, and normal tissues. The technique makes it possible to determine the spatial distribution of glucose, lactate, and ATP in absolute terms at similar locations within tissues or cell aggregates. The substrate distributions are registered in serial cryostat sections from tissue cryobiopsies or from frozen spheroids with the use of bioluminescence reactions. The light emission is measured directly by a special imaging photon counting system enabling on-line image analysis. The technique has been applied to human breast cancer xenografts, to spheroids originating from a human colon adenocarcinoma…
Expression of epithelial antigens EPM-1 and EXO-1 in normal, transitional, inflammatory and neoplastic colorectal mucosa
1993
EPM-1 (a high molecular weight glycoprotein) and EXO-1 (a carbohydrate epitope expressed on polar neutral glycolipids and mucins) are two developmental antigens of normal and neoplastic human epithelia and were characterised by monoclonal antibodies. Their distribution was investigated in normal and pathological human colorectal mucosa. In normal mucosa, EPM-1 and EXO-1 showed characteristic expression patterns. EPM-1 was differentially expressed along the crypt villus axis with maximum at the crypt basis. EXO-1 was present throughout the whole mucosa. The characteristic gradient of EPM-1 expression along the crypt axis in normal mucosa was no longer detectable in benign polyps. Intact grad…
Confocal laser endoscopy: new approach to the early diagnosis of tumors of the esophagus and stomach
2006
The prognosis of malignancies of the upper gastrointestinal tract is poor if early diagnosis is missed. Therefore, a rapid in vivo diagnosis of early cancer and premalignant lesions is highly important for succesful therapy. Confocal laser endomicroscopy allows in vivo cellular and subcellular imaging at high resolutions during ongoing endoscopy. The first studies and clinical observations suggest a major role of this novel technique in the in vivo diagnosis of cancer of the esophagus and stomach and of precursor conditions, such as Barrett’s esophagus, intestinal metaplasia of the stomach and Helicobacter pylori infection. Based on recent experiences from animal models, future studies wil…
Cytoskeletal differences between human neuroendocrine tumors: A cytoskeletal protein of molecular weight 46,000 distinguishes cutaneous from pulmonar…
1985
The cytoskeletons of various human neuroendocrine (NE) tumors were analyzed immunohistochemically using antibodies against intermediate-filament (IF) proteins as well as by two-dimensional gel electrophoresis of proteins from microdissected tissue samples. All of the tumors studied were found to contain cytokeratin filaments and are therefore referred to as 'NE tumors of the epithelial type'. In addition, neurofilaments were found in most cutaneous and some pulmonary NE tumors, as well as in medullary carcinomas of the thyroid and in pancreatic islet cell tumors. The neurofilament staining was frequently concentrated in cytoplasmic IF aggregates. Gel-electrophoretic analyses showed that all…
Italian survey of second tumors in patients with diagnosis of GIST (gastrointestinal stromal tumor).
2019
11032 Background: GISTs are the most common mesenchymal tumors of the digestive tract. As of recent, new links are being made between GISTS and secondary malignancies. However, whether the coexistence of GISTs with other tumors is stochastic, or the result of related pathogenetic mechanisms is still unknown. Methods: We retrospectively reviewed clinical and molecular features from all GIST patients with second tumors treated in seven Italian GIST reference centers. Qualitative variables were compared using the Fisher exact test. Results: Clinical data of 184 patients with diagnosis of GIST were evaluated. Median age at diagnosis was 66 years, KIT exon 11 resulted the most frequent mutation…
The expression of HSP60 and HSP10 in large bowel carcinomas with lymph node metastase
2005
Abstract Background The involvement of Heat Shock Proteins (HSP) in cancer development and progression is a widely debated topic. The objective of the present study was to evaluate the presence and expression of HSP60 and HSP10 in a series of large bowel carcinomas and locoregional lymph nodes with and without metastases. Methods 82 Astler and Coller's stage C2 colorectal cancers, of which 48 well-differentiated and 34 poorly-differentiated, were selected along with 661 lymph nodes, including 372 with metastases and 289 with reactive hyperplasia only, from the same tumours. Primitive tumours and both metastatic and reactive lymph nodes were studied; specifically, three different compartment…
Intestinal epithelial HuR modulates distinct pathways of proliferation and apoptosis and attenuates small intestinal and colonic tumor development.
2014
Abstract HuR is a ubiquitous nucleocytoplasmic RNA-binding protein that exerts pleiotropic effects on cell growth and tumorigenesis. In this study, we explored the impact of conditional, tissue-specific genetic deletion of HuR on intestinal growth and tumorigenesis in mice. Mice lacking intestinal expression of HuR (Hur IKO mice) displayed reduced levels of cell proliferation in the small intestine and increased sensitivity to doxorubicin-induced acute intestinal injury, as evidenced by decreased villus height and a compensatory shift in proliferating cells. In the context of Apcmin/+ mice, a transgenic model of intestinal tumorigenesis, intestinal deletion of the HuR gene caused a three-fo…