Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:Q16637 (SMA)
 8,107 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Most retroperitoneal smooth muscle tumors are believed to be malignant, and leiomyomas are considered very rare. This study was undertaken to determine the clinicopathologic features and long-term follow-up of 56 tumors diagnosed as retroperitoneal leiomyomas (LM) or smooth muscle tumors with an uncertain malignant potential (SMTUMP) in an effort to correlate their behavior and clinicopathologic features. These tumors were compared with a series of 11 cases of retroperitoneal leiomyosarcomas (excluding gastrointestinal stromal tumors). Histologic slides and immunohistochemistry for SMA, desmin, S-100 protein, HMB45, CD34, C-KIT, estrogen (ER) and progesterone (PR) receptor proteins, and MIB-1 were analyzed. All tumors diagnosed as LM and all but one SMTUMP were well-differentiated smooth muscle tumors that lacked atypia and coagulative necrosis. There was <1 mitosis per 50 high power field (HPF) in 38 tumors; no tumor had >3 mitoses/50 HPF. Most tumors had a striking resemblance to uterine smooth muscle tumors with common hyaline change and trabecular patterns. There were 51 females and 5 males ranging in age from 25 to 79 years (mean 45 years, median 43 years). These tumors were typically large, with a mean size of 16.2 cm and weight of 1600 g. Immunohistochemically, all 35 tumors studied were positive for alpha-SMA, 30 of 35 tumors were positive for desmin, and all were negative for CD117, S100 protein, and HMB45 and all but one for CD34. Steroid receptors were commonly present: ER in 20 of 29 cases and PR in 26 of 31 cases in the tumors of female patients. MIB-1 score was <2% in all of 28 cases. Long-term follow-up (mean 140 months) did not reveal metastases, but two patients had local recurrence; however, neither patient with recurrence demonstrated disease progression in follow-up. By contrast, all 11 leiomyosarcomas had at least mild atypia, and all were ER and PR negative. All cases had MIB-1-positive nuclei, but only four had >10% nuclei positive. Four patients died of disease, four were alive with recurrence, and three had no evidence of disease. A group of benign leiomyomas can be identified among retroperitoneal smooth muscle tumors. Most of these tumors resemble uterine leiomyomas by histology and positive hormone receptors, and they seem to have a good long-term prognosis with a small potential for local recurrence.
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PMID:Retroperitoneal leiomyomas: a clinicopathologic and immunohistochemical study of 56 cases with a comparison to retroperitoneal leiomyosarcomas. 1168 51

We describe here--presumably for the first time--a Cajal-like type of tubal interstitial cells (t-ICC), resembling the archetypal enteric ICC. t-ICC were demonstrated in situ and in vitro on fresh preparations (tissue cryosections and primary cell cultures) using methylene-blue, crystal-violet, Janus-Green B or MitoTracker-Green FM Probe vital stainings. Also, t-ICC were identified in fixed specimens by light microscopy (methylene-blue, Giemsa, trichrome stainings, Gomori silver-impregnation) or transmission electron microscopy (TEM). The positive diagnosis of t-ICC was strengthened by immunohistochemistry (IHC; CD117/c-kit+ and other 14 antigens) and immunofluorescence (IF; CD117/c-kit+ and other 7 antigens). The spatial density of t-ICC (ampullar-segment cryosections) was 100-150 cells/mm2. Non-conventional light microscopy (NCLM) of Epon semithin-sections revealed a network-like distribution of t-ICC in lamina propria and smooth muscle meshwork. t-ICC appeared located beneath of epithelium, in a 10-15 microm thick 'belt', where 18+/-2% of cells were t-ICC. In the whole lamina propria, t-ICC were about 9%, and in muscularis approximately 7%. In toto, t-ICC represent ~8% of subepithelial cells, as counted by NCLM. In vitro, t-ICC were 9.9+/-0.9% of total cell population. TEM showed that the diagnostic 'gold standard' (Huizinga et al., 1997) is fulfilled by 'our' t-ICC. However, we suggest a 'platinum standard', adding a new defining criterion- characteristic cytoplasmic processes (number: 1-5; length: tens of microm; thickness: < or =0.5 microm; aspect: moniliform; branching: dichotomous; organization: network, labyrinthic-system). Quantitatively, the ultrastructural architecture of t-ICC is: nucleus, 23.6+/-3.2% of cell volume, with heterochromatin 49.1+/-3.8%; mitochondria, 4.8+/-1.7%; rough and smooth endoplasmic-reticulum (1.1+/-0.6%, 1.0+/-0.2%, respectively); caveolae, 3.4+/-0.5%. We found more caveolae on the surface of cell processes versus cell body, as confirmed by IF for caveolins. Occasionally, the so-called 'Ca2+-release units' (subplasmalemmal close associations of caveolae+endoplasmic reticulum+mitochondria) were detected in the dilations of cell processes. Electrophysiological single unit recordings of t-ICC in primary cultures indicated sustained spontaneous electrical activity (amplitude of membrane potentials: 57.26+/-6.56 mV). Besides the CD117/c-kit marker, t-ICC expressed variously CD34, caveolins 1&2, alpha-SMA, S-100, vimentin, nestin, desmin, NK-1. t-ICC were negative for: CD68, CD1a, CD62P, NSE, GFAP, chromogranin-A, PGP9.5, but IHC showed the possible existence of (neuro)endocrine cells in tubal interstitium. We call them 'JF cells'. In conclusion, the identification of t-ICC might open the door for understanding some tubal functions, e.g. pace-making/peristaltism, secretion (auto-, juxta- and/or paracrine), regulation of neurotransmission (nitrergic/purinergic) and intercellular signaling, via the very long processes. Furthermore, t-ICC might even be uncommitted bipotential progenitor cells.
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PMID:Novel type of interstitial cell (Cajal-like) in human fallopian tube. 1596 70

The report presents 200 cases of gastrointestinal stromal tumors (GIST). The material originated from six diagnostic centers in Poland and was reclassified according to the current criteria. Among lesions other than GISTs, 14 were identified as smooth muscle tumors and seven as neural tumors. GISTs were located in the stomach (51-63.3% of the investigated series), small intestine (27.4-33.8%), colon (approximately 4.5%), abdominal cavity, i.e. in the peritoneum and omentum (6%), and in the retroperitoneal space (2.5%). A slight predominance of women was noted (53-56%). The age of the patients ranged between 14 and 93 years of life, with the mean age of 62.4 years. Individuals younger than 45 years of age accounted for 10% of the group. In ten patients (five of them less than 45 years of life), multiple tumors were detected, their number ranging from two to less than 20; these individuals constituted 5% of the entire series. Moderately and highly aggressive tumors predominated. In the series, when multiple tumors were excluded, a total of 24 epithelioid GISTs (12%) were observed; of this number, 13 were situated in the stomach, six--in the small intestine, two--in the abdominal cavity and another two in the retroperitoneal space. Synchronic tumors observed in patients with GISTs were seen in seven patients, including an adenocarcinoma of the colon, two adenocarcinomas of the stomach, a carcinoid tumor of the small intestine, a pheochromocytoma of the retroperitoneal space, an anaplastic lymphoma and a disseminated squamous cell carcinoma. In immunohistochemical reactions (CD117, CD34, SMA, S-100, DES), attention was focused on the immunoreactivity of small GISTs, below 2 cm in size, and of multiple tumors. Immunohistochemical reactions were equally differentiated as to their presence and intensity in small tumors and in highly aggressive lesions above 5-10 cm in size. In multiple GISTs, immunohistochemical tests strongly indicated the heterogeneity of neoplastic cells, which, nevertheless, showed no consistent association with the location of the tumor, its aggressiveness, cellular structure or a tendency to form multiple foci.
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PMID:Gastrointestinal stromal tumors. A multicenter experience. 1609 66

Gastrointestinal mesenchymal tumors (GIMTs) are the most common mesenchymal tumors of the gastrointestinal tract. RCAS1 (receptor-binding cancer antigen expressed on SiSo cells) is a cancer cell-surface antigen and has been identified as a prognostic factor in several cancer types. It is thought that tumor cells escape immune attack by expressing RCAS1, which induces apoptosis in receptor-positive immune cells. The current study was designed to elucidate the histogenesis of these tumors by using various immunohistochemical markers, and identify parameters that will help to establish the criteria of malignancy in the GIMT. We also discuss the clinicopathological significance of RCAS1 expression in the diagnosis and prognosis of GIMTs. A total of 70 cases of GIMTs were reviewed. Immunohistochemistry was performed between 1990 and 2000, with the avidin-biotin-peroxidase complex method on 3 microm-thick sections of formalin-fixed paraffin-embedded specimens of GIMTs. Antibodies to the following antigens were used: KIT (CD117), CD34 alpha-SMA, Desmin, cytokeratin, S-100 protein, p53, and RCAS1. Recurrence-free survival analysis was done with Stat View-J 5.0 statistical packages. Univariate analysis for a recurrence-free prognosis demonstrated that antibody detection of p53 expression (p=0.0333) and expression of RCAS1 (p=0.0008) is correlated with a significantly higher potential of recurrence. On multivariate analysis, tumor size and RCAS1 expression were independently and inversely correlated with recurrence-free survival. The expression of RCAS1 has not previously been reported in GIMT; indeed, our study suggests that the expression of RCAS1 is correlated with recurrence not only in carcinomas, but also in mesenchymal tumors.
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PMID:A clinical and immunohistochemical study on gastrointestinal mesenchymal tumor (GIMT): RCAS1 as a predictor for recurrence of GIMT. 1621 Dec 75

Malignant gastrointestinal stromal tumors (GIST) are rare mesenchymal tumors originating from the wall of the gastrointestinal tract. Their coexistence with other tumors originating from other germ layers is unique. We have reported a case of a 63-year-old GIST patient presenting as an epigastric mass associated with hepatic tumor. Histologically, the mesenteric tumor was composed of spindle cells showing both neural and smooth muscle differentiation. Immunohistochemical examination showed positive staining for CD117, vimentin, S-100, and SMA, while CD34 antigen was negative. The hepatic tumor was diagnosed as hepatocellular carcinoma (HCC). To the best of our knowledge, this is the first case of GIST and HCC coexistence. The rarity of the case, however, should not lead to ignoring such a possibility in differential diagnosis.
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PMID:Coexistence of hepatocellular carcinoma and gastrointestinal stromal tumor: a case report. 1648 90

Biliary cystadenomas with mesenchymal stroma are neoplasms whose growth may be hormone sensitive. This study profiled the immunohistochemistry of these lesions to clarify the pathophysiology and define clinical management. Twelve patients with biliary cystadenomas were identified. Tissue was tested with a panel of probes including estrogen and progesterone receptors and compared to pancreatic and ovarian cystadenomas. Epithelial ER, PR, CD117, or SMA expression was negative in all three tumors. Epithelial CD10 expression was seen in 60% biliary, 75% pancreatic, and 0% ovarian tumors. Biliary cystadenoma stromal expression was ER+ (70%), PR+ (60%), CD10+ (40%), and c-kit+ (0%). Symptoms were seen in 92% patients. Percutaneous sclerotherapy and incomplete resection were associated with recurrence. Enucleation was the least morbid surgical technique. A role for hormonally mediated growth of biliary cystadenomas occurring through the stroma, rather than the epithelium, is suggested. Management remains complete surgical resection.
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PMID:Biliary cystadenomas: hormone receptor expression and clinical management. 1661 78

Treatment of gastrointestinal stromal tumors (GIST) has been revolutioned by the recently discovered molecular mechanism responsible for the oncogenesis of this disease. In addition, due to the rapid progress at molecular and clinical level observed in the last few years, there is a need to review the current state of the art in order to delineate appropriate guidelines for the optimal management of these tumors. A panel of experts from several specialities, including medical oncology, surgery, pathology, molecular biology and imaging, were invited to participate in a meeting to present and discuss a number of pre-selected questions, and to achieve a consensus according to the categories of the National Comprehensive Cancer Network (NCCN) and the Standard Options Recommandations (SOR) of the French Federation of Cancer Centers. Generally, consensus points were from categories 2A of the NCCN and B2 of the SOR. Conventional histologic examination with immunohistochemistry for CD117, CD34, SMA, S-100 and desmin is considered standard. Molecular analysis for the identification of KIT and PDGFRA mutation may be indicated in CD117-negative GIST. Complete tumor resection with negative margins is the optimal surgical treatment. Adjuvant imatinib should be considered an experimental approach. Neoadjuvant imatinib is also experimental, although its use may be justified in unresectable or marginally resectable GIST. Imatinib should be started in metastatic or recurrent disease, and should be continued until progressive disease or drug intolerance. In these cases, sunitinib can be used. The optimal criteria for the assessment and monitoring of GIST undergoing imatinib therapy are not well known, but they should include reduction in tumor size and disease stabilization, as well as reduction of tumor density on CT scan and metabolic activity on PET scan.
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PMID:[Clinical guidelines for the management of gastrointestinal stromal tumors]. 1690 Aug 56

CD34+ fibrocytes are constitutive elements of the connective tissue where they play a role in matrix synthesis and tumor-associated stromal remodeling. Secreted protein, acidic, and rich in cysteine (SPARC) is a pivotal mediator of stromal remodeling precipitated by invasive carcinomas. The present study was undertaken to investigate CD34+ fibrocytes in the stroma of the tumor-free urinary bladder, chronic cystitis, and urothelial carcinomas together with stromal expression of alpha-smooth muscle actin (alpha-SMA), CD117, and SPARC. In tumor-free urinary bladder and chronic cystitis, CD34+ fibrocytes were found in the deep lamina propria and tunica muscularis, whereas the superficial lamina propria disclosed a CD34-negative and alpha-SMA-positive fibrocyte-like cell. Invasive urothelial carcinomas revealed a complete loss of CD34+ fibrocytes and concomitant appearance of alpha-SMA-reactive myofibroblasts which showed strong expression of SPARC. CD117 expression of tumor-free and tumor-associated stroma revealed no differences. We in this study for the first time describe CD34+ fibrocytes in the urinary bladder and an up-to-now unknown population of alpha-SMA-positive fibrocytes exclusively occurring in the superficial lamina propria. Stromal remodeling associated with invasive carcinomas in the urinary bladder is characterized by a loss of CD34+ fibrocytes paralleled by a gain of alpha-SMA-positive myofibroblasts and increased expression of SPARC.
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PMID:CD34+ fibrocytes in chronic cystitis and noninvasive and invasive urothelial carcinomas of the urinary bladder. 1714 10

Gastro-intestinal stromal tumours (GIST) are a biologically distinct heterogenous group of tumours of the gut. They are said to arise from interstitial cells of Cajal in gut wall. The turnour results from mutation of c-kit gene which codes for CD117 containing tyrosine kinase receptor of Cajal cells. Identification of this mutation by immunohistochemistry (IHC) is the key to the diagnosis of these tumours. CD117 negative GISTs develop from gene mutation through alternate pathway (PDGFRA). The accurate diagnosis is important as specific chemotherapeutic agents are now available for their management. We have studied 8 cases of GISTs during last 2 years in our institute. Half of the cases were female, six cases were in the age group between 35 to 50 years, the other two being of 19 and 70 years. On histology, 5 cases were categorized as high grade on the basis of their size and mitotic count. All cases were subjected to IHC. Only 4 cases were CDll7 positive, one case was positive for S100 and one case for SMA. Remaining 2 cases, negative for CD117, S100 and SMA, histologically resembled GISTs. CD117 positive cases are ideal candidates for treatment with molecularly targeted specific chemotherapeutic agents, e.g., imatinib as these tumours are non-responsive to conventional chemotherapy. Histologically diagnosed stromal tumours of the gut should be subjected to immunostain for CD117 so that specific medical management can be provided to prevent recurrence and metastasis as well as pre-operative debulking of the tumour.
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PMID:Gastro-intestinal stromal tumour--role of CD117 in diagnosis and management. 1788 45

Skeinoid fibers are globular, brightly eosinophilic periodic Schiff stain (PAS)-positive extracellular collagen deposits commonly seen in gastrointestinal stromal tumors (GIST) of the small bowel. However, smooth-surfaced hyaline globules are occasionally encountered in leiomyomatous GI neoplasms and may be mistaken for true skeinoid fibers. We investigated a total of 93 histologically and immunohistochemically well-characterized true smooth muscle neoplasms of the GI tract for the presence of hyaline globules. A variable number of PAS-positive intracellular and interstitial hyaline globules were detected in all benign paucicellular leiomyomas of the muscularis mucosae (n=72) and the muscularis propria (n=14) irrespective of tumor size and site, but in none of leiomyosarcomas (n=7) and cellular leiomyoma (n=1). In addition, similar findings were rarely seen in the adjacent muscularis propria. Similar to surrounding tumor cells, hyaline globules expressed desmin, alpha-SMA, and h-caldesmon, but were negative for CD117 and CD34. Ultrastructural examination revealed altered filamentous material in different stages of degeneration with variably condensed matrix and occasional peripheral condensation suggestive of calcification. True skeinoid fibers were not detected. The above findings are consistent with a multistep degenerative phenomenon affecting individual smooth muscle cells in paucicellular GI leiomyomas. Awareness of this finding would prevent misinterpretation as GIST, particularly in small biopsies.
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PMID:Hyaline globules in paucicellular leiomyomas of the gastrointestinal tract are distinct from skeinoid fibers and represent degenerating smooth muscle cells. 1921 34


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