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)

MECs are distributed on the basal aspect of the intercalated duct and acinus of human and rat salivary glands. However, they do not occur in the acinus of rat parotid glands, and sometimes occur in the striated duct of human salivary glands. MECs, as the name implies, have structural features of both epithelial and smooth muscle cells. They contract by autonomic nervous stimulation, and are thought to assist the secretion by compressing and/or reinforcing the underlying parenchyma. MECs can be best observed by immunocytochemistry. There are three types of immunocytochemical markers of MECs in salivary glands. The first type includes smooth muscle protein markers such as alpha-SMA, SMMHC, h-caldesmon and basic calponin, and these are expressed by MECs and the mesenchymal vasculature. The second type is expressed by MECs and the duct cells and includes keratins 14, 5 and 17, alpha 1 beta 1 integrin, and metallothionein. Vimentin is the third type and, in addition to MECs, is expressed by the mesenchymal cells and some duct cells. The same three types of markers are used for studying the developing gland. Development of MECs starts after the establishment of an extensively branched system of cellular cords each of which terminates as a spherical cell mass, a terminal bud. The pluripotent stem cell generates the acinar progenitor in the terminal bud and the ductal progenitor in the cellular cord. The acinar progenitor differentiates into MECs, acinar cells and intercalated duct cells, whereas the ductal progenitor differentiates into the striated and excretory duct cells. Both in the terminal bud and in the cellular cord, the immediate precursors of all types of the epithelial cells appear to express vimentin. The first identifiable MECs are seen at the periphery of the terminal bud or the immature acinus (the direct progeny of the terminal bud) as somewhat flattened cells with a single cilium projecting toward them. They express vimentin and later alpha-SMA and basic calponin. At the next developmental stage, MECs acquire cytoplasmic microfilaments and plasmalemmal caveolae but not as much as in the mature cell. They express SMMHC and, inconsistently, K14. This protein is consistently expressed in the mature cell. K14 is expressed by duct cells, and vimentin is expressed by both mesenchymal and epithelial cells. After development, the acinar progenitor and the ductal progenitor appear to reside in the acinus/intercalated duct and the larger ducts, respectively, and to contribute to the tissue homeostasis. Under unusual conditions such as massive parenchymal destruction, the acinar progenitor contributes to the maintenance of the larger ducts that result in the occurrence of striated ducts with MECs. The acinar progenitor is the origin of salivary gland tumors containing MECs. MECs in salivary gland tumors are best identified by immunocytochemistry for alpha-SMA. There are significant numbers of cells related to luminal tumor cells in the non-luminal tumor cells that have been believed to be neoplastic MECs.
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PMID:Immunocytochemistry of myoepithelial cells in the salivary glands. 1450 96

Tissue engineering of heart valves utilizes biodegradable or metabolizable scaffolds for remodeling by seeded autologous cells. The aim of this study was to determine and compare extracellular matrix (ECM) formations, cellular phenotypes and cell location of native and tissue engineered (TE) valve leaflets. Ovine carotid arteries, ovine and porcine hearts were obtained from slaughterhouses. Cells were isolated from carotid arteries and dissected ovine, porcine and TE leaflets. TE constructs were fabricated from decellularized porcine pulmonary valves, seeded ovine arterial cells and subsequent 16 days dynamic in vitro culture using a pulsatile bioreactor. Native and TE valves were studied by histology (hematoxylin-eosin, resorcin-fuchsin, Movat pentachrome), NIR femtosecond multiphoton laser scanning microscopy and scanning electron microscopy (SEM). Cells of native and TE tissues were identified and localized by immunohistochemistry. Arterial, valvular and re-isolated TE-construct cells were processed for immunocytochemistry and Western blotting. ECM analysis and SEM revealed characteristical and comparable structures in native and TE leaflets. Most cells in native leaflets stained strongly positive for vimentin. Cells positive to alpha-smooth muscle actin (alpha-SMA), myosin and calponin were only found at the ventricular (inflow) side of ovine aortic and porcine pulmonary valve leaflets. Cells from TE constructs had a strong expression of vimentin, alpha-SMA, myosin, calponin and h-caldesmon throughout the entire leaflet. Comparable ECM formation and endothelial cell lining of native and TE leaflets could be demonstrated. However, immunostaining revealed significant differences between valvular cell phenotypes of native and TE leaflets. These results may be essential for further cardiovascular tissue engineering efforts.
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PMID:Comparative study of cellular and extracellular matrix composition of native and tissue engineered heart valves. 1524 10

The spindle cell variant of rhabdomyosarcoma (RMS) is uncommon and is most often encountered in the paratesticular region of children in whom it has a good prognosis. Only isolated cases in adulthood have been described. Sixteen cases of spindle cell RMS occurring in adults were retrieved from our files. Eleven patients were male and 5 were female. Patient age ranged from 18 to 79 years (median, 32 years). Tumor size varied from 1.5 to 35 cm (median, 6 cm). The head and neck region, including the oral cavity, parotid gland, nasopharynx, and nasal cavity, was the commonest affected area, accounting for >50% of the cases, followed by retroperitoneum, thigh, leg, subscapular area, hand, vulva, and paratesticular region (1 case each). Follow-up was available in 12 cases, ranging from 1 to 102 months (median, 16.5 months). Treatment modalities included surgery, chemotherapy, and radiation. Two patients died of uncontrolled local disease 13 and 27 months after diagnosis; 4 were alive without disease at 12, 17, 24, and 102 months, including 1 patient with metastasis to 10 of 50 pelvic lymph nodes at presentation; 3 are alive with localized disease at 16, 17, and 19 months; and 1 was followed for 6 months and showed persistent local disease. One patient is alive at 10 months after diagnosis with evidence of metastatic disease to bone, lungs, and breast. All the tumors showed long fascicles of spindle cells with elongated, vesicular nuclei and pale indistinct cytoplasm. Scattered spindled or polygonal rhabdomyoblasts with abundant brightly eosinophilic cytoplasm were present in all cases. In 3 cases, focal areas showed pseudovascular, sclerosing features. There were no round cell or pleomorphic areas. Positive immunohistochemical results were as follows: desmin (15 of 15 cases), myf-4 (12 of 12), fast myosin (7 of 9), myoglobin (2 of 3), HHF-35 (9 of 9), and SMA (11 of 14). One tumor was focally positive for keratins and EMA. All tumors were negative for caldesmon, S-100 protein, and GFAP. Spindle cell RMS is a rare neoplasm in adults and appears to have distinct clinicopathologic features when compared with cases occurring in the pediatric population. Specifically, it appears to be most common in the head and neck region, and although only limited follow-up is available so far, these lesions appear to have a more aggressive clinical course in adults.
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PMID:Spindle cell rhabdomyosarcoma in adults. 1600 7

Nodular fasciitis is a benign myofibroblastic proliferation with a predilection for the subcutaneous tissues of the upper extremities, trunk, and head and neck of young adults. Nodular fasciitis is not generally recognized to arise within joints. In this study, the clinicopathologic and immunohistochemical features of 10 cases of intraarticular nodular fasciitis are described. Six patients were female and 4 were male, with a median age of 33 years (range, 9-50 years). Lesional size ranged from 2 to 4 cm (median, 2.6 cm). Seven tumors arose in the knee, 2 in the hand, and 1 in the ankle. Most patients complained of joint pain; 4 presented with a palpable mass. Only 1 patient reported antecedent trauma. The duration of symptoms prior to surgery ranged from 2 months to 1 year (median, 6 months). The clinical differential diagnoses included giant cell tumor of tendon sheath, pigmented villonodular synovitis, synovial chondromatosis, inflammatory arthritis, and lymphoma. Grossly, the lesions were solid, nodular, rubbery, or firm masses. Histologically, all tumors were circumscribed but unencapsulated and showed typical features of nodular fasciitis, being composed of cytologically bland plump spindle cells arranged in short, intersecting bundles within a variably loose myxoid to collagenous stroma, containing extravasated red blood cells and scattered lymphocytes. Five lesions showed prominent stromal hyalinization, in 2 cases keloidal in appearance. In 4 cases, the tissue at the periphery of the lesion showed hemosiderin deposition. By immunohistochemistry, all tumors examined were positive for SMA, 1 was positive for desmin, and all were negative for caldesmon and S-100 protein; none showed nuclear staining for beta-catenin. Clinical follow-up information was available for 5 patients, ranging from 2 to 86 months. No lesion recurred. In summary, intraarticular nodular fasciitis occurs most commonly in the knees of young adults, and often appears to have a somewhat longer preoperative duration than typical subcutaneous or intramuscular nodular fasciitis. Intraarticular lesions show morphologic features similar to other cases of nodular fasciitis, with the exception that stromal hyalinization and adjacent hemosiderin deposition are common, likely attributable to frictional trauma in this location.
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PMID:Intraarticular nodular fasciitis--a rare lesion: clinicopathologic analysis of a series. 1643 99

We present an extensive immunohistochemical analysis of 7 mammary sarcomas that did not fit into any specific soft tissue sarcoma category. Histologically, they were composed of spindle cells with highly pleomorphic nuclei and abundant mitoses. Our immunohistochemical antibody panel included pan-cytokeratin (CK), basal cell type CKs (34betaE12, CK5/6, CK14, CK17) and vimentin antibodies, antibodies to established (SMA, CD10, p63, S-100, maspin, calponin, GFAP, SM-myosin), and novel (CD29, 14-3-3sigma) myoepithelial markers, as well as antibodies to CD34, desmin, h-caldesmon, steroid receptors (estrogen, progesterone, androgen), and EGFR (Her-1). Whereas CKs, CD34, desmin, and h-caldesmon were not expressed, all tumors were positive for CD10 and vimentin. CD29 and SMA were observed in 3 cases each (43%), and p63 and calponin in 2 cases each (29%). Other myoepithelial markers and steroid receptors were absent, except androgen receptors, which were expressed in one sarcoma. Five sarcomas showed positivity for EGFR. The distinction of specific, histogenetically defined sarcoma entities (such as leiomyosarcoma, angiosarcoma, liposarcoma) from NOS-type sarcoma with CD10 expression is usually clear-cut because the former exhibit a characteristic histomorphology and immunoprofile. Phyllodes tumors with stromal overgrowth or recurrent phyllodes tumors lacking epithelial structures as well as periductal stromal sarcomas can be ruled out by their frequent expression of CD34 and negativity for myoepithelial markers. The most important differential diagnosis is sarcomatoid metaplastic carcinoma because its treatment includes axillary lymphadenectomy. Since some NOS-type sarcomas with CD10 expression and most metaplastic carcinomas show positivity for CD29, SMA, and p63, differential diagnosis can be extremely difficult and requires extensive immunohistochemical evaluation for CKs and additional myoepithelial markers such as S-100, 14-3-3sigma, and maspin. The immunophenotype of NOS-type sarcomas with CD10 expression suggests that these neoplasms represent a mammary sarcoma variant with myoepithelial features.
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PMID:Mammary NOS-type sarcoma with CD10 expression: a rare entity with features of myoepithelial differentiation. 1662 90

The objective of this study was to determine whether cyclic strain could promote human umbilical vein endothelial cells (HUVECs) to express markers in common with the mature smooth muscle cell (SMC) phenotype, suggesting endothelial cell to SMC transdifferentiation. HUVECs were cultured on stretched membranes at 10% stretch and 60 cycles/min for 24-96 hr, and demonstrated elongation with enhanced and organized F-actin distribution. By using real-time polymerase chain reaction analysis, the mRNA levels of five specific SMC markers, SM22-alpha, alpha-smooth muscle actin (alpha-SMA), caldesmon-1, smooth muscle myosin heavy chain (SMMHC), and calponin-1 were significantly increased in cyclic strain-treated HUVECs as compared with those in static control cells. Protein levels of SM22-alpha and alpha-SMA were also substantially increased by Western blot and immunofluorescence staining. In addition, two specific endothelial markers, von Willebrand factor (vWF) and vascular endothelial growth factor receptor-2 (VEGFR-2), showed a reduction in mRNA expression. In addition, cyclic strain-induced increase of SM22-alpha and alpha-SMA expression were reversible when cells were cultured back to the static condition. These results demonstrate a possible endothelial cell to SMC transdifferentiation in response to cyclic strain. Hemodynamic forces in modulating endothelial phenotype may play an important role in the vascular system.
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PMID:Cyclic strain induces expression of specific smooth muscle cell markers in human endothelial cells. 1717 52

We report a 40-year-old lady who presented with severe headaches, persistent microscopic haematuria and hypertension requiring anti-hypertensive medication. Investigations for secondary hypertension were all normal except for a CT scan. This indicated a complex cystic lesion, measuring 2.4 x 5 x 10 cms , arising from the right kidney. She underwent an open right partial nephrectomy. The patient made an un-eventful postoperative recovery and her blood pressure returned to normal. The mass had a smooth outer surface and the cut surface showed firm whitish tissue with a few small cysts. Microscopy showed a bland spindle cell lesion staining positively for SMA, desmin, caldesmon, focally for HMB45 amd very focally for S100. The mass was reported as a Perivascular Epitheloid Cell (PEC) lesion (PEComa) arising from the renal capsule. Perivascular Epitheloid Cell tumor (PEComa), a recently defined tumor, is extremely rare. The lesion presents a distinct muscular immunophenotype (actin+, desmin+), with co-expression of the melanogenesis marker (HMB45). This combined immunophenotype is a characteristic feature of the Perivascular Epitheloid Cell (PEC) lesions. PEComa's are usually benign, but cases have been reported in the literature which has an unfavourable outcome with metastatic dissemination. We report this case because of its rarity and also Renal Capsular PEComa should be considered as a rare cause of renal hypertension, which can be surgically cured.
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PMID:Renal capsular PEComa--a rare cause of surgically correctable renal hypertension. 1731 50

Inflammatory myofibroblastic tumor (IMT) and low-grade myofibroblastic sarcoma (LGMS) are intermediate- or low-grade malignant myofibroblastic neoplasms. In this study, the clinicopathologic profiles of 24 IMTs and 10 LGMS were compared with a focus on the immunohistochemical profiles of the neoplastic myofibroblasts. The primary antibodies used in this study were specific for the ultrastructural subcellular components: (1) *-smooth muscle actin (*-SMA), muscle-specific actin (MSA), calponin, and h-caldesmon for myofilaments; (2) fibronectin for fibronexus; (3) laminin for basal lamina; (4) desmin and cytokeratin for intermediate filaments. Anaplastic lymphoma kinase (ALK) alterations were examined by immunohistochemical means, with selective fluorescence in situ hybridization analysis. Histologically, IMT had inhomogeneous microscopic features with multi-component and multi-patterned architecture, whereas LGMS tended to be more uniform in appearance with a higher cellularity, more prominent nuclear hyperchromasia, and a more widely infiltrative growth pattern than IMT. Immunohistochemically, firstly, more than 90% of the cases of both IMT and LGMS expressed calponin, *-SMA, MSA, and fibronectin, almost all with a high expression level, and no cases were positive for h-caldesmon. Secondly, 33.3% (7/21) of IMTs and 40% (4/10) of LGMS were positive for desmin with a low expression level. The positive percentage for laminin was 81.8% (18/22) in IMT, but was 42.9% (3/7) in LGMS with a low expression level. Thirdly, 13.6% (3/22) of IMTs were positive for cytokeratin, but no expression was found in LGMS. ALK staining was found in 40.9% (9/22) of IMTs, and the presence of ALK gene rearrangements was confirmed by fluorescence in situ hybridization in 5 of 6 IMTs examined. However, neither ALK gene rearrangements nor ALK protein labeling was detected in LGMS (0/9). In summary, IMT and LGMS are both composed of cells displaying well-developed myofibroblastic differentiation, which frequently and extensively express actin-associated proteins (*-SMA, MSA, and calponin) and fibronectin, consistent with the ultrastructure markers (myofilaments and fibronectin fibrils). Laminin expression does not exclude a diagnosis of myofibroblastic neoplasms. ALK and cytokeratin, when positive, can be helpful in differentiating IMT from LGMS. LGMS is not a member of the family of ALK-positive tumors.
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PMID:Inflammatory myofibroblastic tumor and low-grade myofibroblastic sarcoma: a comparative study of clinicopathologic features and further observations on the immunohistochemical profile of myofibroblasts. 1840 Feb 54

Angiotensin II (Ang II) is involved in the development of cardiovascular disease and vascular remodeling. In this study, we demonstrate that treatment of human adipose tissue-derived mesenchymal stem cells (hADSCs) with Ang II increased the expression of smooth muscle-specific genes, including alpha-smooth muscle actin (alpha-SMA), calponin, h-caldesmon, and smooth muscle myosin heavy chain (SM-MHC), and also elicited the secretion of transforming growth factor-beta1 (TGF-beta1) and delayed phosphorylation of Smad2. The Ang II-induced expression of alpha-SMA and delayed phosphorylation of Smad2 were blocked by pretreatment of the cells with a TGF-beta type I receptor kinase inhibitor, SB-431542, small interference RNA-mediated depletion of endogenous Smad2, and adenoviral expression of Smad7. Furthermore, the Ang II-induced TGF-beta1 secretion, alpha-SMA expression, and delayed phosphorylation of Smad2 in hADSCs were abrogated by the MEK inhibitor U0126, suggesting a pivotal role of MEK/ERK pathway in the Ang II-induced activation of TGF-beta1-Smad2 signaling pathway. The smooth muscle-like cells which were differentiated from hADSCs by Ang II treatment exhibited contraction in response to 60mM KCl. These results suggest that Ang II induces differentiation of hADSCs to contractile smooth muscle-like cells through ERK-dependent activation of the autocrine TGF-beta1-Smad2 crosstalk pathway.
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PMID:Angiotensin II-induced differentiation of adipose tissue-derived mesenchymal stem cells to smooth muscle-like cells. 1857 60

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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