Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.17 (lysozyme)
 21,489 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

By immunoperoxidase analysis for types I to VI collagen, elastin, cytoskeletal components and some glycoproteins, we found type VI collagen immunoreactivity in amorphous eosinophilic deposits (skeinoid fibers) in three small intestinal stromal tumors. Negative results were obtained for types I, II, III, IV and V collagen, elastin, laminin, ubiquitin, intracellular filaments such as actin, desmin, vimentin, calponin and caldesmon, and glycoprotein such as lysozyme, factor XIIIa, beta2-microglobulin, alpha1-antitrypsin and alpha1-antichymotrypsin. In two lesions, the periodic acid-Schiff-positive skeinoid fibers were also focally labeled for amyloid P component.
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PMID:Type VI collagen immunoreactivity in skeinoid fibers in small intestinal stromal tumors. 1050 58

Angiomatoid "malignant" fibrous histiocytoma (AMFH) has been considered to be a low-grade sarcoma of childhood, and, with its fibrous pseudocapsule, angiomatoid change, dense lymphoplasmacytic response, and proliferation of spindled or round cells, has been classified as a fibrohistiocytic neoplasm. We wanted to study the clinicopathologic and immunophenotypic features of a large number of these tumors and to especially further explore their myoid differentiation. Cases coded as AMFH from 1979 to 1995 were retrieved from the Soft Tissue Registry of the AFIP. Only cases that met the criteria for AMFH by light microscopy were included, a total of 158 cases. Immunohistochemistry was obtained on 98 cases. Clinical history on 92% of all cases revealed a gender ratio of 1.3 females: males, age range of 2 to 71 years, median size of 2.0 cm, and a distribution of extremities > trunk > head and neck, with 66% lesions occurring in areas of normal lymphoid tissue. All tumors with available margins were well-circumscribed. Eighty percent of cases had some degree of lymphoplasmacytic infiltration; 50% cases had pseudovascular spaces filled with blood. Fifty-two percent had predominantly round cell morphology; 48% had a predominantly spindle cell pattern. Desmin positivity was noted in 51% cases and occurred in both predominantly round cell and spindle cell tumors. Most of the desmin-positive cases with adjacent lymphoid infiltrate (67%) showed scattered similar, desmin-positive cells in the surrounding lymphoid infiltrate, adjacent to the tumor. Muscle-specific and smooth-muscle actins were seen in 14% cases. Heavy-caldesmon was strongly positive in 3%, and calponin was focally positive in 73% and extensively positive in 12% cases. MyoD1, myoglobin, and myogenin (myf4) were negative in all tumors studied. Forty-five percent of cases were positive for CD99; 52% of these had round cell morphology. Fifteen percent of cases were positive for KP-1. All tumors were positive for vimentin and negative for CD21, CD35, S100 protein, CD34, keratins 8/18, and lysozyme. Clinical follow-up on 86 patients indicated that only 1 patient was alive with a local nodal metastasis (1% frequency of metastasis) within 1 year, and 2 others had local recurrence, all over a mean follow-up period of 6 years. The myoid, primarily myofibroblastic, phenotype of these lesions is supported by desmin, calponin, and occasional actin positivity. The occasional heavy-caldesmon and smooth muscle actin additionally suggest rare smooth muscle phenotype; however, lack of skeletal muscle markers indicate no relationship of AMFH to skeletal muscle tumors. The resemblance of these lesions to lymph nodes, clinically and morphologically, the finding of similar desmin positive cells in the adjacent lymphoid infiltrate, and the fact that 66% cases were found in sites of normal lymphoid tissue raise the possibility that some of these lesions may arise from or be related to myoid cells of lymphoid tissue. AMFH has an almost invariably benign behavior, but the 1% metastatic rate warrants its classification as low-grade "malignant." The predominantly round cell, CD99-positive and desmin positive AMFH cases, respectively, should not be confused with Ewing's sarcoma/PNET or rhabdomyosarcoma, respectively.
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PMID:Angiomatoid "malignant" fibrous histiocytoma: a clinicopathologic study of 158 cases and further exploration of the myoid phenotype. 1057 14

We address the clinicopathologic features of a previously undescribed heavily-pigmented spindle cell proliferation within a circumscribed benign lipomatous lesion that occurs mainly in the ankle region of older females. Patients with "lipoma with fibrohistiocytic proliferation" were retrieved from our files. Slides and clinical information were reviewed, and immunohistochemistry was performed (n = 5). Ten patients with hemosiderotic fibrohistiocytic lipomatous lesions were identified. All cases demonstrated a well-circumscribed fatty lesion with random focal proliferations of plump, slightly pleomorphic spindled cells, scattered inflammatory cells, and abundant iron pigment. The spindled cells had vesicular nuclei with indistinct nucleoli; occasional hyperchromatism was observed. No nuclear cytoplasmic inclusions were identified. The spindled component had a reactive appearance. In most cases, the fatty component, with homogeneously sized adipocytes, predominated. The lesions occurred in the foot/ankle region (8/10, one each cheek and hand) of primarily females (8/10) with a mean age of 50.6 years (range 42-63 years), size of 7.7 cm (range 2.5-17 cm), and prior duration of 3.1 years. Seven of eight patients had a history of prior trauma. The spindled component was positive for vimentin, calponin, CD34, and occasionally KP-1 or lysozyme and negative for caldesmon, S100, and desmin. Follow-up on eight patients revealed four with recurrences or residual disease over three years, requiring re-excision. No cases metastasized or caused patient death (mean 12 years, range 1-23 years). We describe a predominantly fatty lesion that is hemosiderin rich with a "fibrohistiocytic" proliferation, composed of histiocytes, myofibroblasts, and C34-positive fibroblasts, which occurs predominantly in the ankle region of middle-aged females. We believe that this is a reactive process due to antecedent trauma, the inflammatory cells, hemosiderin, mixed spindled cells, and homogeneous non-neoplastic appearance of the fat. HFLL can be distinguished from previously described lesions. Correct identification of hemosiderotic fibrohistiocytic lipomatous lesion is important, as it may locally recur.
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PMID:Hemosiderotic fibrohistiocytic lipomatous lesion: ten cases of a previously undescribed fatty lesion of the foot/ankle. 1110 76

A lipoma with a spindled proliferation within it, resembling known (myo)fibroblastic lesions such as fibrous histiocytoma or dermatofibrosarcoma protuberans, (ie, fibrohistiocytic lipoma), has not been previously reported. This tumor varies from other classic lipoma variants, including spindle cell lipoma, myolipoma, angiolipoma, and fibrolipoma. We examine the clinicopathologic findings of this new lipoma variant. The Soft Tissue Pathology Registry of the Armed Forces Institute of Pathology was searched for patients with "lipoma with fibrohistiocytic proliferation." Lesions that were better classified as other entities were excluded. Patient slides and clinical history, including associated lesions, family history, duration of symptoms, history of trauma, natural progression, and treatments, were reviewed. Immunohistochemistry was performed on cases with available material (n = 6). Twelve patients with fibrohistiocytic lipoma were included. All tumors revealed a well-distributed quilt-like proliferation or solid focus of slightly plump to relatively bland spindled cells with collagenous stroma in short fascicular and storiform growth patterns. These spindled cells resembled those seen in either fibrous histiocytoma or dermatofibrosarcoma protuberans. However, the spindled proliferation was all within a well-circumscribed lipoma. The lesions lack the dermal involvement or plump pleomorphism of fibrous histiocytoma and the dermal involvement or infiltrative growth pattern of dermatofibrosarcoma protuberans. The fatty component demonstrated heterogeneously sized adipocytes, as those seen in other lipomas. Inflammation and hemosiderin were minimal. Mast cells were not identified. The tumors were typically found in the subcutis of the trunk of men (10 of 12; one each on the wrist and leg; mean age, 31 years). The average size of the lesions was 3.0 cm, and they were present for a mean duration of 10 months prior to surgical excision. One patient had two concurrent lesions; all others had solitary tumors. Another patient had a intracranial dermoid cyst removed during childhood. Four patients had a personal or family history of hypercholesterolemia, hypertension, or myocardial infarction. There was no history of antecedent trauma. Cases studied were positive for vimentin, calponin (5 of 5), CD34 (3 of 5), and occasionally KP-1 or lysozyme in the spindled component, and all cases studied were negative for the actins, caldesmon, S-100 protein, desmin, cytokeratins, and epithelial membrane antigen. Although the actins were negative in our laboratory, the more sensitive calponin positivity suggests myofibroblastic phenotype of the spindled component of this lesion. CD34-positive fibroblasts were present in three of five cases. Of eight patients with follow-up, there were no recurrences; all patients were alive and free of disease over a mean of 10 years (range, 2 months to 31 years). We have identified a lipoma variant, fibrohistiocytic lipoma, that has not been previously described. In our experience the morphology and calponin positivity suggest myofibroblastic phenotype for the spindled cells, within a lipoma. This entity can be distinguished from fibrous histiocytoma, fibromatosis, dermatofibrosarcoma protuberans, spindle cell lipoma and other lipoma, and liposarcoma variants.
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PMID:Fibrohistiocytic lipoma: twelve cases of a previously undescribed benign fatty tumor. 1114 65

Cutaneous clear cell tumors are a heterogeneous group of cutaneous neoplasms, which may show a wide range of histogenesis. We report the clinicopathological features of an agminated clear cell tumor, arising in a 67-year-old man, otherwise asymptomatic, with distinct histopathological and immunohistochemical features, which did not fit into any existing diagnostic categories. The patient presented with several skin-colored papules at the lateral and posterior aspects of the neck, which on histopathological examination showed circumscribed lobular aggregates of clear cells within the dermis. The immunohistochemical marker panel performed showed diffuse expression of vimentin, NKI-C3, and CD64 while revealing marked negativity for factor XIIIa, CD10, CD13, CD14, CD34, CD68, CD163, lysozyme, HMB45, Renal Cell Carcinoma antigen, calponin, h-caldesmon, Anti-alpha smooth muscle actin antibody [1 A4], S100, and pancytokeratin, leading the authors to postulate a monocytic origin.
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PMID:Agminated Clear Cell Tumor: An Impostor of PEComa and Distinctive Dermal Clear Cell Mesenchymal Neoplasm. 2782 2