Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Microcystic adenoma (serous cystadenoma) of the pancreas (MA) is an unusual benign tumor of uncertain histogenesis. We have studied 14 cases of MA from 11 women and three men. The average age at diagnosis was 64 years. Six tumors were discovered incidentally. Tumors varied from 2.5 to 12 cm in greatest dimension and all were multicystic; eight tumors were located in the pancreatic head, two in the body, and three in the tail. Each tumor was composed of variably sized cysts lined by simple cuboidal or flattened, focally glycogen-rich epithelium. The stroma was variably collagenized and showed highly vascularized, delicate to broad fibrous septae, which focally contained dystrophic calcification, cholesterol clefts, and hemosiderin. Immunohistochemical studies were performed on eight cases to determine the cell of origin. Epithelial membrane antigen and a low-molecular-weight keratin, detected by monoclonal antibodies PKK1 or AE1/AE3, were diffusely seen in tumor cells of all cases. Tumor cells were uniformly negative for carcinoembryonic antigen, chromogranin, insulin, glucagon, somatostatin, vasoactive intestinal peptide, pancreatic polypeptide, and a low-molecular-weight keratin detected by monoclonal antibody PKK2. Tumor cell antigen reactivity most resembled that seen in normal centroacinar and ductal cells. Electron microscopy of seven cases showed primitive tumor cells with irregularly spaced, short, blunt microvilli, luminal occluding junctions and belt desmosomes, bundles of filaments including dense bodies in both apical and basal cell cytoplasm, sparse organelles, and variable but often pronounced amounts of glycogen. These ultrastructural features most closely resembled the normal pancreatic centroacinar cell. Based on both immunohistochemical and ultrastructural features described above, we conclude that the centroacinar cell is the cell of origin of MA.
 ...
PMID:Microcystic adenoma (serous cystadenoma) of the pancreas. A study of 14 cases with immunohistochemical and electron-microscopic correlation. 335 51

Giant cell carcinoma of the vulva has been described as a distinctive primary tumor of the vulva associated with multinucleated tumor giant cells and nuclear pleomorphism. These tumors have been reported to have a poorer prognosis than does squamous cell carcinoma, to which they are thought to be related. Two women were treated for primary vulvar malignancies possessing the morphologic features of giant cell tumor. Electron microscopy was not beneficial in distinguishing the tumors. A panel of immunoperoxidase procedures, including AE 1/3, 35 beta H-11, carcinoembryonic antigen, epithelial membrane antigen, HMB-45, S-100, leukocyte common antigen, placentalike alkaline phosphatase, alpha-1-antichymotrypsin and vimentin made it possible to distinguish the two tumors and characterized one as a nodular amelanotic melanoma with multinucleate tumor giant cells and the second as a squamous cell carcinoma with tumor giant cells. The latter term should replace the term giant cell carcinoma. Histologic criteria can help define this tumor.
 ...
PMID:Two distinct pathologic types of giant cell tumor of the vulva. A report of two cases. 340 13

Cultures of rat palatal epithelium grown on collagen rafts were treated with different doses of the potent tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA). Sections from biopsies taken 1, 6, 24, and 48 hr after the addition of TPA were examined for the localization of staining by blood group antigen H antibody and antikeratin antibody AE1. In contrast to control cultures, where antigen H was seen exclusively at the cell membranes of the second and third cell layer, several antigen H-positive cells, some appearing in groups, were found in the basal cell layer of TPA-treated specimens. Staining for keratins with the AE1 antikeratin antibody showed no staining of basal cells but only suprabasal cells in controls, whereas several cells of the basal cell layer of TPA-treated cultures stained positively with this antibody. The results support the theory that TPA, by forcing a part of the basal cell population to terminal differentiation, strongly affects the composition of the basal cell population.
 ...
PMID:The tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA) accelerates expression of differentiation markers in cultures of rat palatal epithelial cells. 348 73

Human epidermal keratinocytes express under various growth conditions a total of at least nine keratins that can be divided into two subfamilies. Subfamily A comprises 40-, 46-, 48-, 50-/50'-, and 56.5-kilodalton (kd) keratins which are relatively acidic (pI less than 5.5) and, with the exception of 46-kd keratin, are recognized by AE1 monoclonal antibody. Subfamily B comprises 52-, 56-, 58-, and 65-67-kd keratins which are relatively basic (pI greater than 6) and are recognized by AE3 monoclonal antibody. Within each keratin subfamily, there is a constant member (50-/50'- and 58-kd keratins of the subfamilies A and B, respectively) that is always expressed. The other seven keratins of both subfamilies are variable members whose expression depends upon the cellular differentiated state, which is in turn modulated by the growth environment. The 56.5-kd keratin (subfamily A) and the 65-67-kd keratins (subfamily B) are coordinately expressed during keratinization. In contrast, the 40-, 46-, and 48-kd keratins (subfamily A) and the 52- and 56-kd keratins (subfamily B) are characteristic of cultured epidermal cells forming nonkeratinized colonies. These results demonstrate that human epidermal keratins can be classified according to their reactivity with monoclonal antikeratin antibodies, isoelectric point, and mode of expression. The classification of keratins into various subgroups may have important implications for the mechanisms of epidermal differentiation, the evolution of keratin heterogeneity, and the use of keratin markers for tumor diagnosis.
 ...
PMID:Classification of epidermal keratins according to their immunoreactivity, isoelectric point, and mode of expression. 620 91

Nasopharyngeal carcinoma (NPC) provides a unique opportunity to evaluate distinctive epidemiologic features and a possible etiologic relationship with Epstein-Barr virus (EBV) in human malignancy. The lack of a uniformly accepted pathologic classification for NPC has limited the application of this data, although the World Health Organization (WHO) developed a classification that may solve this problem. Monoclonal keratin antibodies were used for staining of NPC for evaluation of its assistance in diagnosis and classification. In the present immunohistochemical study, monoclonal keratin antibodies, designated AE1, AE2, and AE3, and a polyclonal keratin antibody (RAK) were used for study of the presence of keratin in 121 cases of NPC obtained from China and the United States. AE1 monoclonal antibody, which recognizes keratin protein classes 56.5K, 50K, and 40K, was shown to be the most sensitive and specific for NPC tumor cells among the keratin antibodies studied. In addition, some different keratin expression patterns could be identified between different kinds of epithelium and different tumor groups, with possible relevance to the histogenesis of the histologic subtypes of NPC.
 ...
PMID:Immunohistochemical study of nasopharyngeal carcinoma using monoclonal keratin antibodies. 620 35

Previous studies have indicated that some Simian-virus-40-transformed human epidermal keratinocytes (SV40-HE) undergo significant changes in their growth and differentiated properties. To better understand the significance of these changes, we have characterized the keratins of SV40-HE cells by one- and two-dimensional immunoblot analysis using the subfamily-specific AE1 and AE3 monoclonal antikeratin antibodies. The results indicate that our SV40-HE cells have lost the Mr 58,000 (No. 5), Mr 56,000 (No. 6), Mr 50,000 (No. 14/15), Mr 48,000 (No. 16), and Mr 46,000 (No. 17) keratins that are expressed by cultured normal human keratinocytes. Instead, these cells express mainly Mr 52,000 (No. 8), Mr 45,000 (No. 18), and Mr 40,000 (No. 19) keratins, a set highly characteristic of simple epithelial cells. Furthermore, our SV40-HE cells have ceased to express involucrin, another marker for keratinocytes, and have a greatly diminished ability to undergo in vitro stratification. These results suggest that epidermal cells can sometimes lose their keratinocyte features as a consequence of viral transformation. This finding may have important implications regarding the mechanisms of epithelial differentiation and tumorigenesis and in the use of keratinocyte markers for tumor diagnosis.
 ...
PMID:Simple epithelial nature of some simian virus-40-transformed human epidermal keratinocytes. 620 4

Twenty-two benign pleomorphic adenomas of the major salivary glands were studied by transmission electron microscopy and immunohistochemical techniques (three cases) in order to characterize the cell types comprising the epithelial and so-called mesenchymal regions of the tumors. Light- and electron-microscopic studies showed the tumors to consist of variable mixtures of neoplastic ductular epithelial cells, rare acinar cells, and metaplastic myoepithelial cells. Many of the loosely organized "stromal cells" contained structures indicative of their myoepithelial origin, e.g., perinuclear tonofilaments, ectoplasmic actin microfilaments, and remnants of basement membrane. Polyclonal antikeratin antisera strongly stained ductular epithelial and myoepithelial cells, squamoid cell nests, and periductular myoepithelial cells, whereas myxoid and chondroid cells were less intensely stained. Monoclonal cytokeratin antibody AE1 stained only the ductular epithelial cells in both the normal glands and tumors. In contrast, S-100 protein, which is present only in scattered acinar cells and myoepithelial cells in the normal parotid gland, was found in the ductular and periductular myoepithelial cells, isolated myxoid cells, and chondroid and cartilagenous cells in the tumors. Actin was found in all the cell types of the tumor but staining was strongest in the ducts. Double immunofluorescence staining for cytokeratin and vimentin revealed coexpression of both types of intermediate filaments in occasional normal acinar and intercalated duct myoepithelial cells, and in some cells in the myxoid and chondroid regions of the tumors. In the tumors, vimentin was present in occasional periductular myoepithelial cells, stellate myxoid cells, and especially in chondroid cells and chondrocytes. Our findings indicate that benign pleomorphic adenomas of the major salivary glands are pure epithelial cell tumors. The histologic complexity of these neoplasms is due to the ability of the neoplastic ductular myoepithelial cell to modulate its morphologic appearance and intermediate filament composition, and to produce large amounts of matrix substances. We further postulate that these tumors arise from neoplastically transformed intercalated ducts.
 ...
PMID:Histogenesis of benign pleomorphic adenoma (mixed tumor) of the major salivary glands. An ultrastructural and immunohistochemical study. 620 92

The typical example of malignant fibrous histiocytoma (MFH) or dermatofibrosarcoma protruberans (DFSP) does not require ancillary studies for diagnosis. However, hemorrhage with cystic change consisting of blood-filled spaces may closely mimic a vascular neoplasm. Eight fibrohistiocytic sarcomas exhibiting these angiomatoid features, initially mistaken for vascular neoplasms, were identified from personal consultation files and review of 157 consecutive sarcomas (1985 through 1993) at the University of California-(Davis) Medical Center. They included five MFH giant-cell-type sarcomas, two MFH angiomatoid-type sarcomas, and one DFSP. Immunohistochemical analysis of paraffin-embedded material showed vimentin diffuse positive, CD68 (KP-1) diffuse positive, and factor VIII negative in all eight sarcomas; actin HHF-45 focal positive in six, diffuse positive in one, and negative in one sarcoma; desmin focal positive in two and negative in six sarcomas; and S100 protein, cytokeratin AE1:AE3, cytokeratin 10.11, and EMA negative in all eight sarcomas. Electron microscopy of three tumors exhibited neoplastic cells with fibroblastic, myofibroblastic, and histiocytic features. Weibel-Palade bodies or neolumens diagnostic of vascular differentiation were absent. The clinical characteristics and behavior of these sarcomas reflect entities in the spectrum of fibrohistiocytic lineage (MFH subtypes and DFSP) rather than vascular neoplasms. Patients with deep, large, giant-cell-type MFHs did poorly (two of four patients died from disease at 8 and 25 months). Both patients with angiomatoid MFHs showed local recurrences from large incompletely excised head and neck lesions. One died of disease at 21 months and the other is free of disease 12 months following excision of a local metastasis to the opposite side of the neck. The patient with DFSP had an 18-cm locally recurrent scalp tumor that extended into bone. Immunohistochemical and ultrastructural confirmation of fibroblastic, myofibroblastic, and histiocytic lineage and exclusion of vascular differentiation help to establish the correct diagnosis in these fibrohistiocytic sarcomas with angiomatoid features. The clinicopathologic features of these eight cases reaffirm the practical utility of MFH and DFSP as diagnostic entities in the spectrum of fibrohistiocytic sarcomas.
 ...
PMID:Angiomatoid features in fibrohistiocytic sarcomas. Immunohistochemical, ultrastructural, and clinical distinction from vascular neoplasms. 748 9

Six intrascrotal, invasive epithelial neoplasms of serous papillary type arose in the paratesticular region of patients 16 to 42 (mean, 30.8) years of age. Five patients, one with an associated hydrocele, presented with a testicular mass and one with a hydrocele only. The serum CA-125 level was elevated in one of the two patients in whom it was measured. Grossly, the tumors were solid, white, or tan, poorly circumscribed, often gritty masses. Four tumors involved primarily the soft tissue between the testis and epididymis (testiculoepididymal groove) and one, the paratesticular soft tissue. The sixth tumor was confined to the visceral tunica vaginalis at the inferior pole of the testis. The most common microscopic pattern was characterized by invasive, well-formed papillae lined by serous cuboidal or columnar cells with eosinophilic cytoplasm and malignant nuclear features. Psammoma bodies were abundant in all the cases. Areas of borderline serous tumor were present in two tumors and predominated in one. Five of five tumors were positive for keratin (AE1/3), S-100, epithelial membrane antigen, and Ber-EP4; three of five for Leu M1 and B72.3; two of five for carcinoembryonic antigen and placental alkaline phosphatase; and one in five for vimentin. Ultrastructural examination in one case demonstrated gland formation with delicate luminal microvilli and cilia. Follow-up information was available in five cases: Three patients are without evidence of disease after relatively short postoperative intervals of 1, 1, and 3 years, although one of these patients has had a persistently elevated CA-125 level. Two patients had recurrence of their tumors 4 and 7 years after diagnosis, one with diffuse abdominal spread, the other in a cervical lymph node. The latter patient died of his disease 5 years after diagnosis.
 ...
PMID:Paratesticular serous papillary carcinoma. A report of six cases. 750 58

An increasing interest in fish species as sentinels of environmental pollution and in carcinogenesis research has led to the identification of diagnostically challenging neoplasms of uncertain cellular origin and the need for additional diagnostic methods. To determine the potential of using commercially available antibodies to intermediate filament proteins on paraffin-embedded fish tissues for immunocytochemistry in tumor diagnosis, the application of three antikeratin antibodies to normal adult tissues from two fish species was assessed. Multiple tissues from 12-14-in. striped bass (Morone saxatilis) and 6-month-old medaka (Oryzias latipes) of both sexes were fixed in Bouin's or formalin fixatives. Formalin-fixed neoplasms from several mammalian species, including cat, dog, hedgehog (Atelerix albiventris, Erinaceus europaeus), rhesus macaque (Macaca mulatta), and sloth bear (Melursus ursinus), were also used as positive controls. Using a strepavidin horseradish peroxidase method on paraffin-embedded tissues, the broad spectrum antibodies AE1/AE3 (Boehringer Mannheim, Indianapolis, IN) and MAK-6 (Triton Biosciences, Alameda, CA), which recognize most of the 19 human cytokeratins, and CAM 5.2 (Becton Dickinson, Mountain View, CA), which recognizes cytokeratins present in human liver, were used as primary antibodies. Epithelia from skin, gills, cornea, bile ducts, renal tubules, gastrointestinal tract, and thymus were strongly positive with AE1/AE3 and MAK-6 in striped bass, but nonepithelial tissues such as bone and muscle were negative. Skin, gills, cornea, and portions of the gastrointestinal tract were strongly positive in medaka with the same antibodies, whereas bile duct, renal, and intestinal epithelia were less so. Tissue digestion improved the intensity of staining, and fixation with Bouin's fixative improved results somewhat compared with formalin fixation.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:The immunocytochemistry of cytokeratin in fish tissues. 750 8


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>