Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P10721 (c-kit)
 6,575 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We describe a hitherto undocumented variant of dimorphic pituitary neoplasm composed of an admixture of neurosecretory cells and profuse leiomyomatous stroma around intratumoral vessels. Radiologically perceived as a macroadenoma of 3.8 cm in diameter, this pituitary mass developed in an otherwise healthy 43-year-old female. At the term of a yearlong history of amenorrhea and progressive bitemporal visual loss, subtotal resection was performed via transsphenoidal microsurgery. Discounting mild hyperprolactinemia, there was no evidence of excess hormone production. Histologically, solid sheets, nests and cords of epithelial-looking, yet cytokeratin-negative cells were seen growing in a richly vascularized stroma of spindle cells. While strong immunoreactivity for NCAM, Synaptophysin and Chromogranin-A was detected in the former, the latter showed both morphological and immunophenotypic hallmarks of smooth muscle, being positive for vimentin, muscle actin and smooth muscle actin. Architectural patterns varied from monomorphous stroma-dominant zones through biphasic neuroendocrine-leiomyomatous areas, to pseudopapillary fronds along vascular cores. Only endothelia were labeled with CD34. Staining for S100 protein and GFAP, characteristics of sustentacular cells, as well as bcl-2 and c-kit was absent. Except for alpha-subunit, anterior pituitary hormones tested negative in tumor cells, as did a panel of peripheral endocrine markers, including serotonin, somatostatin, calcitonin, parathormone and vasoactive intestinal polypeptide. Mitotic activity was absent and the MIB-1 labeling index low (1-2%). While assignment of this lesion to any established neoplastic entity is not forthcoming, we propose it is being considered as a low-grade neuroendocrine tumor possibly related to null cell adenoma.
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PMID:Leiomyomatoid angiomatous neuroendocrine tumor (LANT) of the pituitary: a distinctive biphasic neoplasm with primitive secretory phenotype and smooth muscle-rich stroma. 1652 Sep 66

We have previously reported (Hinescu & Popescu, 2005) the existence of interstitial Cajal-like cells (ICLC), by transmission electron microscopy, in human atrial myocardium. In the present study, ICLC were identified with non-conventional light microscopy (NCLM) on semi-thin sections stained with toluidine blue and immunohistochemistry (IHC) for CD117/c-kit, CD34, vimentin and other additional antigens for differential diagnosis. Quantitatively, on semi-thin sections, ICLC represent about 1-1.5% of the atrial myocardial volume (vs. approximately 45% working myocytes, approximately 2% endothelial cells, 3-4% for other interstitial cells, and the remaining percentage: extracellular matrix). Roughly, there is one ICLC for 8-10 working atrial myocytes in the intercellular space, beneath the epicardium, with a characteristic (pyriform, spindle or triangular) shape. These ICLC usually have 2-3 definitory processes, emerging from cell body, which usually embrace atrial myocytes (260 nm average distance plasmalemma/sarcolemma) or establish close contact with nerve fibers or capillaries (approximately 420 nm average distance to endothelial cells). Cell prolongations are characteristic: very thin (mean thickness = 0.15+/-0.1 microm), very long for a non-nervous cell (several tens of microm) and moniliform (uneven caliber). Stromal synapses between ICLC and other interstitial cells (macrophages) were found (e.g. in a multicontact type synapse, the average synaptic cleft was approximately 65 nm). Naturally, the usual cell organelles (mitochondria, smooth and rough endoplasmic reticulum, intermediate filaments) are relatively well developed. Caveolae were also visible on cell prolongations. No thick filaments were detected. IHC showed that ICLC were slightly and inconsistently positive for CD117/c-kit, variously co-expressed CD34 and EGF receptor, but appeared strongly positive for vimentin, along their prolongations. Some ICLC seemed positive for a-smooth muscle actin and tau protein, but were negative for nestin, desmin, CD13 and S-100. In conclusion, we provide further evidence of the existence of ICLC in human atrial myocardium, supporting the possible ICLC role in pacemaking, secretion (juxta- and/or paracrine), intercellular signaling (neurons and myocytes). For pathology, ICLC might as well be 'players' in arrhythmogenesis and atrial remodeling.
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PMID:Interstitial Cajal-like cells (ICLC) in atrial myocardium: ultrastructural and immunohistochemical characterization. 1656 37

Chemotherapy in itself is suspected to cause the development or selection of drug-resistant tumor cells, which have more aggressive phenotypes. The authors investigated the differential changes of gene expression in the 1-(4-amino-2-methyl-5-pyrimidinyl)-methyl-3-(2-chloroethyl)-3-nitrosourea (ACNU)-resistant subline of the C6 rat glioma (C6AR2), which was established from C6 rat glioma cells by exposure to ACNU in vitro. The resistance to ACNU of C6AR2 was confirmed by MTS assay. The increased expression of O6-methylguanine-DNA methyltransferase in C6AR2 cells was shown using RT-PCR. C6AR2 cells displayed a higher proliferative activity relative to C6 cells. Analysis with cDNA array showed that 19 genes were transcriptionally up-regulated and 16 genes down-regulated in C6AR2 cells compared to C6 cells. They belonged to various functional classes of genes beside the drug-resistant system. Among them, the down-regulation of several genes in C6AR2 cells, including c-kit, pleiotrophin, platelet-derived growth factor receptor-alpha, peripheral myelin protein-22 and NG2 chondroitin sulfate proteoglycan, which are expressed originally in developmental glial lineages, were verified using semi-quantitative RT-PCR. In addition, the gene expression of astroglial intermediate filament proteins, including GFAP, vimentin and nestin, were decreased in C6AR2 cells relative to C6 cells in semi-quantitative RT-PCR and immunocytochemistry. These findings may represent an undifferentiated state of ACNU-resistant glioma cells and a more aggressive phenotype in recurrent tumors following chemotherapy.
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PMID:Gene expression profiles of 1-(4-amino-2-methyl-5-pyrimidinyl)-methyl-3-(2-chloroethyl)-3-nitrosourea (ACNU)-resistant C6 rat glioma cells. 1664 21

Primary primitive neuroectodermal tumours (PNETs) of the bladder are extremely rare and aggressive neoplasms, and only six examples have been reported in the literature. The case of a 21-year-old woman, who remains disease free 3 years after tumour resection, is reported here. Morphological features were found to correspond to a small round blue cell tumour without rosette formation and with extensive areas of necrosis. Strong expression of CD99, vimentin and CD117 (c-kit), and focal reactivity to cytokeratin and S-100 protein was observed in tumour cells. Ultrastructurally, sparse neurosecretory granules were observed. Diagnosis of PNET was supported by molecular genetic analysis, showing the EWS-FLI-1 fusion transcript type 2 by RT-PCR and EWS gene rearrangement by fluorescence in situ hybridisation. A normal genetically balanced genotype was shown by comparative genomic hybridisation, which, together with the expression of c-kit, a known therapeutic target for imatinib, may have prognostic and therapeutic implications.
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PMID:Primary primitive neuroectodermal tumour of the urinary bladder: a clinico-pathological study emphasising immunohistochemical, ultrastructural and molecular analyses. 1680 53

The expression of vimentin, alpha-smooth muscle actin (alpha-SMA) and c-kit in adenoid cystic carcinomas (AdCCs) and polymorphous low-grade adenocarcinomas (PLGAs) was investigated immunohistochemically to evaluate the application of these markers to distinguish AdCCs from PLGAs when the histological features are equivocal. Tissue specimens of AdCCs and of PLGAs, formalin-fixed and paraffin-embedded were retrospectively studied using vimentin, alpha-SMA and c-kit. Positive staining for alpha-SMA was identified in all AdCCs and 25% of PLGAs. The immunoreactivity of c-kit in all positive cases of AdCCs (83%) and PLGAs (41%) was more than 50% and less than 50% of tumor cells respectively. The expression pattern for both alpha-SMA and c-kit, in tubular structures of AdCCs was different of that seen in the same structures in PLGAs. The results of this study support the potential application of alpha-SMA and c-kit as an adjunctive aid in the differential diagnosis of AdCCs from PLGAs.
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PMID:Application of alpha-smooth muscle actin and c-kit in the differential diagnosis of adenoid cystic carcinoma from polymorphous low-grade adenocarcinoma. 1680 72

The basal phenotype of breast carcinoma was demonstrated from a study of gene expression profiles, which demonstrated five carcinoma phenotypes with differing immunohistologic profiles and outcomes. The basal phenotype, so-named because of an immunohistologic profile that is similar to myoepithelial cells of the breast, has poor outcomes. While the invasive basal phenotype has been described, there is a paucity of literature regarding the existence or recognition of a precursor lesion. We searched our CoPath database for breast carcinomas in the age group of 37 years or less, and this yielded 98 cases from the years 2001 to April 2006. Pathology reports were screened for those cases that were negative for estrogen and progesterone receptors and HER-2/neu (triple negative). A total of 16 cases (16/98, 16%) fulfilled these criteria. Histology was reviewed and immunostains were performed for Cytokeratins 14, 17, and 5/6, vimentin, EGFR, c-kit, smooth muscle actin and p63. All 16 cases had a high-grade invasive ductal carcinoma, Nottingham score 9/9, with geographic necrosis, good circumscription and lymphoid infiltrates. Of the 16 cases, 13 exhibited at least one area of ductal carcinoma in situ (DCIS). The DCIS types were solid, flat or micropapillary, high nuclear grade, with comedonecrosis and invariably associated with intense lymphoid inflammatory cell infiltration. Of 16 invasive cases, 14 (88%) were positive for CK14, CK17, CK5/6 and EGFR; 94% were vimentin positive, while half or less of cases were positive for smooth muscle actin, c-kit or p63. All of the DCIS components demonstrated the same immunohistologic profile as the invasive component. A DCIS component of solid, flat or micropapillary type exists in the basal phenotype of breast carcinoma, and it demonstrates the same immunophenotype as the invasive carcinoma, typically positive for CK5/6, CK14, CK17, vimentin and EGFR, but negative for ER/PR and HER-2/neu.
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PMID:Basal phenotype of ductal carcinoma in situ: recognition and immunohistologic profile. 1694 Oct 11

To further define the clinicopathologic spectrum of epithelial-myoepithelial carcinoma (EMCa), we report the gross, histologic, and immunophenotypic characteristics of 61 tumors seen within a 30-year-period. The mean age at presentation was 60.9 years, with a female predominance (1.5:1). The most common sites were parotid (62.1%), sinonasal mucoserous glands (10.3%), palate (8.6%), and submandibular (8.6%). Most EMCas showed a characteristic nodular/multinodular growth pattern and classic biphasic tubular histology. However, new morphologies in EMCa such as ancient change (8.2%), "Verocay"-like change (3.3%), and sebaceous differentiation (13.1%) were noted. Specific histologic variants were dedifferentiated EMCa (3.3%), oncocytic EMCa (8.2%), EMCa ex pleomorphic adenoma (1.6%), double-clear EMCa (3.3%), and EMCa with myoepithelial anaplasia (3.3%). All cytokeratin cocktails selectively highlighted the epithelial component well. Of the myoepithelial markers, p63, smooth muscle actin and vimentin performed best. Bcl-2 and c-kit were frequently positive (66.7% and 69.2%, respectively). p53 was highly expressed only in 1 dedifferentiated EMCa. The recurrence rate was 36.3% (median disease-free survival 11.34 y), but death was rare with 5-year and 10-year disease-specific survivals of 93.5% and 81.8%, respectively. The most important univariate predictors of recurrence were margin status (log rank P=0.006), angiolymphatic invasion (P=0.002), tumor necrosis (P=0.004), and myoepithelial anaplasia (P=0.038). Thus, EMCa is generally a low-grade tumor with a broader morphologic spectrum than previously thought, with several key features predictive of recurrence. Immunohistochemistry can aid diagnosis by highlighting the biphasic nature of the tumor.
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PMID:Epithelial-myoepithelial carcinoma: a review of the clinicopathologic spectrum and immunophenotypic characteristics in 61 tumors of the salivary glands and upper aerodigestive tract. 1719 18

Preoperative diagnosis of hepatic angiomyolipoma is difficult, and the treatment for it remains controversial. The aim of this study is to review our experience in the treatment of hepatic angiomyolipoma and to propose a treatment strategy for this disease. We retrospectively collected the clinical, imaging, and pathological features of patients with hepatic angiomyolipoma. Immunohistochemical studies with antibodies for HMB-45, actin, S-100, cytokeratin, vimentin, and c-kit were performed. Treatment experience and long-term follow-up results are summarized. During a period of 9 years, 10 patients with hepatic angiomyolipoma were treated at our hospital. There was marked female predominance (nine patients). Nine patients received surgical resection without complications. One patient received nonoperative management with biopsy and follow-up. One patient died 11 months after surgery because of recurrent disease. We propose all symptomatic patients should receive surgical resection for hepatic angiomyolipoma. Conservative management with close follow-up is suggested in patients with asymptomatic tumors and meet the following criteria: (1) tumor size smaller than 5 cm, (2) angiomyolipoma proved through fine needle aspiration biopsy, (3) patients with good compliance, and (4) not a hepatitis virus carrier.
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PMID:Management of hepatic angiomyolipoma. 1743 29

Penile malignancies are rare in developed countries. The authors present a case of a penile urethral mesenchymal tumor occurring in a 51-year-old Caucasian male and displaying light microscopic, immunohistochemical, and ultrastructural features suggestive of a pacemaker cell type, combined with a lack of diagnostic features of any other established tumor category. The immunohistochemical profile was intensely positive for vimentin, PKC theta, and NSE and weakly positive to nonreactive for CD34 and smooth muscle actin, and entirely negative for CD117 (c-kit), S-100, and other markers. C-kit and PDGFRA gene analysis showed no mutations. Electron microscopy revealed tumor cells with plentiful cytoplasm and cytoplasmic processes/filopodia, both filled with intermediate filaments and occasional solitary focal densities. There were also prominent smooth endoplasmic reticulum cisternae, caveolae, neurosecretory granules, particularly concentrated in cytoplasmic processes, and synaptic-type structures. Poorly formed basal lamina, gap junctions, and intercellular collagen aggregates, consistent with skeinoid-type fibers, were also noted. Interstitial cells with potential pacemaker function have been recently described in the lower urinary tract, including the urethra, and this tumor may be related to this cellular phenotype.
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PMID:Urethral stromal tumor with pacemaker cell phenotype. 1745 99

Perivascular epithelioid cell tumor (PEComa) is defined as a very rare mesenchymal tumor of histologically and immuno-histochemically distinctive perivascular epithelioid cells. PEComa in the colon is very rare, with only a few reported cases so far. Because of its rarity, the clinical features and biological behavior of PEComa in the colon have yet to be established. A 16-year-old female patient with PEComa in the transverse colon was referred to our hospital for rectal bleeding. Laboratory data showed a hemoglobin level of 6.6 g/dL, WBC of 8,800/mm(3), and platelet count of 191,000/mm(3). Colonoscopy, barium enema, and abdominal computed tomography revealed a 2-cm, smooth-surfaced, round tumor with focal ulceration in the proximal transverse colon. The patient complained of abdominal pain one day after endoscopic polypectomy. She underwent a segmental resection for a perforated transverse colon. Immunohistochemically, the tumor cells showed strong diffuse positivity for HMB-45 while they were negative for c-kit, smooth muscle actin, cytokeratin, S-100, vimentin, desmin, chromogranin, synaptophysin, EMA, and CD-34. The diagnosis of PEComa was based on histological and immunohistochemical staining. The patient did not receive any adjuvant therapy and was discharged on postoperative day 11 without complications. Whole-body fluorine-18 fluorodeoxyglucose fusion positron emission tomography performed 2 months after surgery showed no signs of recurrence or metastasis. There was also no recurrence or metastasis at 24 months' follow-up.
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PMID:Perivascular epithelioid cell tumor (PEComa) in the transverse colon of an adolescent: a case report. 1745 82


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