Search results for "ADENOMAS"
showing 10 items of 12 documents
DNA methylation changes and somatic mutations as tumorigenic events in Lynch syndrome-associated adenomas retaining mismatch repair protein expression
2018
Background: DNA mismatch repair (MMR) defects are a major factor in colorectal tumorigenesis in Lynch syndrome (LS) and 15% of sporadic cases. Some adenomas from carriers of inherited MMR gene mutations have intact MMR protein expression implying other mechanisms accelerating tumorigenesis. We determined roles of DNA methylation changes and somatic mutations in cancer-associated genes as tumorigenic events in LS-associated colorectal adenomas with intact MMR. Methods: We investigated 122 archival colorectal specimens of normal mucosae, adenomas and carcinomas from 57 LS patients. MMR-deficient (MMR-D, n 49) and MMR-proficient (MMR-P, n 18) adenomas were of particular interest and were inter…
Gene Expression (mRNA) Markers for Differentiating between Malignant and Benign Follicular Thyroid Tumours
2017
Distinguishing between follicular thyroid cancer (FTC) and follicular thyroid adenoma (FTA) constitutes a long-standing diagnostic problem resulting in equivocal histopathological diagnoses. There is therefore a need for additional molecular markers. To identify molecular differences between FTC and FTA, we analyzed the gene expression microarray data of 52 follicular neoplasms. We also performed a meta-analysis involving 14 studies employing high throughput methods (365 follicular neoplasms analyzed). Based on these two analyses, we selected 18 genes differentially expressed between FTA and FTC. We validated them by quantitative real-time polymerase chain reaction (qRT-PCR) in an independe…
Molecular alterations in lesions of anogenital mammary-like glands and their mammary counterparts including hidradenoma papilliferum, intraductal pap…
2017
Lesions affecting anogenital mammary-like glands (AGMLG) are histopathologically very similar to those seen in the breast but whether this morphological similarity is also reflected at the genetic level is unknown. To compare the underlying molecular mechanisms in lesions of AGMLG and their mammary counterparts, we analyzed the mutational profile of 16 anogenital neoplasms including 5 hidradenomas papilliferum (HP), 1 lesion with features of HP and fibroadenoma (FA), 7 FA, 3 phyllodes tumors (PhT)) and 18 analogous breast lesions (6 intraductal papillomas (IDP), 9 FA, and 3 PhT) by high-coverage next generation sequencing (NGS) using a panel comprising 50 cancer-related genes. Additionally,…
Myoepithelial cells are the main component in pleomorphic adenomas?
2007
Objective: The aim of this study was to quantify by immunohistochemistry the number of myoepithelial cells (MyECs) in pleomorphic adenomas (PAs). Material and methods: We retrieved the paraffin cubes of 27 PAs, new slides were done and they were stained with anti-S100 protein antibody. The amount of S-100 protein positive cells was quantified, their morphology was recorded and comparison among MyEC number with age, gender and involved gland were also done. Results: With S-100 protein, MyECs in normal salivary gland tissue were seen surrounding the ductual structures only. In the analysed PAs a mean of 27.4% of the neoplastic cells were positive to the antibody. With the exception of one PA,…
Development and validation of the SIMPLE endoscopic classification of diminutive and small colorectal polyps
2018
Abstract Background Prediction of histology of small polyps facilitates colonoscopic treatment. The aims of this study were: 1) to develop a simplified polyp classification, 2) to evaluate its performance in predicting polyp histology, and 3) to evaluate the reproducibility of the classification by trainees using multiplatform endoscopic systems. Methods In phase 1, a new simplified endoscopic classification for polyps – Simplified Identification Method for Polyp Labeling during Endoscopy (SIMPLE) – was created, using the new I-SCAN OE system (Pentax, Tokyo, Japan), by eight international experts. In phase 2, the accuracy, level of confidence, and interobserver agreement to predict polyp hi…
Comparison between a guaiac and three immunochemical faecal occult blood tests in screening for colorectal cancer
2012
Abstract Background The aim of this study was to compare the performance of the guaiac-based faecal occult blood test (G-FOBT), with that of three immunochemical faecal occult blood tests (I-FOBT) which allow automatic interpretation. Patients and methods Under the French organised screening programme, 85,149 average-risk individuals aged 50–74 participating in the third screening round, performed both the G-FOBT (Hemoccult-II test) and one of the I-FOBTs: FOB-Gold, Magstream and OC-Sensor. Results Given the chosen threshold, the positivity ratio between the different I-FOBTs and the G-FOBT was 2.4 for FOB-Gold, 2.0 for Magstream and 2.2 for OC-Sensor (P = 0.17). The three I-FOBTs were supe…
Coexpression of IL-6 and soluble IL-6R causes nodular regenerative hyperplasia and adenomas of the liver
1998
Studies with tumor necrosis factor p55 receptor- and interleukin-6 (IL-6)-deficient mice have shown that IL-6 is required for hepatocyte proliferation and reconstitution of the liver mass after partial hepatectomy. The biological activities of IL-6 are potentiated when this cytokine binds soluble forms of its specific receptor subunit (sIL-6R) and the resulting complex interacts with the transmembrane signaling chain gp130. We show here that double transgenic mice expressing high levels of both human IL-6 and sIL-6R under the control of liver-specific promoters spontaneously develop nodules of hepatocellular hyperplasia around periportal spaces and present signs of sustained hepatocyte prol…
Visa genoma asociācija identificē ģenētiskos marķierus, kas saistīti ar hipofīzes adenomas risku un fenotipu
2019
Visa genoma asociācijas pētījumi(GWAS) ir pētījumu metode noteikta klīniskā stāvokļa ģenētiskā cēloņa noskaidrošanai, izmantojot genotipēšanas mikromasīvus un SNP nelīdzsvarotās saistības principu. Hipofīzes adenomas(HA) ir nemetastazējoši audzēji ar dažādu molekulāro izcelsmi. Līdz šim zināmas vairākas somatiskas mutācijas (GNAS, MEN1, USP8, GPR101), kas asociētas ar noteiktu HA klīnisko tipu klātbūtni, kā arī veikti kandidātgēnu pētījumi HA ģenētisko cēloņu noteikšanai. Līdz šim pasaulē veikts tikai viens GWAS pētījums, lai konstatētu ar HA tumoroģenēzi asociētos SNP Ķīnas Han populācijā. Šajā darbā izmantoja 233 HA un 468 kontroles indivīdu genotipus, tika noteikti ar palielinātu hipofīz…
Corticotroph aggressive pituitary tumours and carcinomas frequently harbour ATRX mutations
2021
Abstract Context Aggressive pituitary tumors (APTs) are characterized by unusually rapid growth and lack of response to standard treatment. About 1% to 2% develop metastases being classified as pituitary carcinomas (PCs). For unknown reasons, the corticotroph tumors are overrepresented among APTs and PCs. Mutations in the alpha thalassemia/mental retardation syndrome X-linked (ATRX) gene, regulating chromatin remodeling and telomere maintenance, have been implicated in the development of several cancer types, including neuroendocrine tumors. Objective To study ATRX protein expression and mutational status of the ATRX gene in APTs and PCs. Design We investigated ATRX protein expression by us…
Centrālās nervu sistēmas ietekme uz adenohipofīzes adenomu attīstību
2015
Adenohipofīzes adenomas ir labdabīgi intrakraniāli endokrīnie audzēji ar potenciāli augstu prevalenci populācijā. To rašanās rezultātā pacientiem var attīstīties plaša spektra veselības problēmas. Bakalaura darbā veikta adenohipofīzes adenomu šūnu izpēte, analizējot to proliferāciju un saistību ar CNS. Darba gaitā tika konstatētas dažādas CNS cilmes šūnām raksturīgās īpašības adenomu paraugos.