Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027627 (metastases)
 103,950 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A case of a feminizing adrenocortical tumor associated with Cushing's syndrome in a 29 year old male is presented. The ultrastructural features are compared with adrenal tumors secreting aldosterone, glucocorticoids of androgens. As in adrenal carcinomas, this tumor demonstrates nuclear pleomorphism with enlarged nucleoli and nuclear pseudoinclusions. The cytoplasmic organelles show some parallels between feminizing and androgen-secreting adrenal tumors. Different types of mitochondria occur with varying amounts of smooth endoplasmic reticulum. Numerous microbodies are present. Histological and ultrastructural signs indicating probably malignancy are discussed and it is noted that most of the feminizing adrenal tumors are carcinomata. Neither local recurrence nor distant metastases have yet been detected in this case, two years after excision of the tumor.
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PMID:Feminizing adrenocortical tumor. Histological and ultrastructural study. 20 8

The lesions that appear during hepatocarcinogenesis can be separated into morphologically distinct entities, which have been arranged into sequences believed to represent stages in carcinogenesis. Similarly, the primary and transplantable hepato-cellular carcinomas (HCC) can be arranged into a sequence of stages believed to represent the progression toward the ultimate cancer cell. Separation of morphological entities has been most successful in rat liver. Ultrastructural studies differentiate between lesions derived from hepatocytes and those originating in other cellular components of the liver. They show that there is variability and divergence in the structure of cellular organelles in the early stages of carcinogenesis, that there is simplification of cellular structure and of organelles during the progression of HCC, and that qualitative changes specific for cancer cells do not exist. Toxic changes associated with the process of carcinogenesis are loss of stacks; wrapping of cisternae around mitochondria; dilation, denudation, and vesiculation of cisternae; increase of autophagy; depletion of glycogen, and enlargement of nuclei and nucleoli. Early changes are storage of glycogen and hyperplasia of smooth endoplasmic reticulum. Subsequent alterations are increased variability in the size, shape, and structure of mitochondria and in the structure of endoplasmic reticulum, including the appearance of fingerprints. A transient stage recognizable by storage of lipid may represent a degenerative process. Ultrastructural characteristics of basophilic cells such as abundance of free ribosomes and absence of glycogen and of smooth endoplasmic reticulum suggest that they may be a stage in the formation of HCC. Progression of HCC is associated with a decrease in the number and size of mitochondria, reduction of mitochondrial cristae, decrease in the number and complexity of microbodies, reduction of the tubulovesicular form of smooth reticulum, accumulation of free ribosomes, and increase of the granular component and condensation of the fibrillar component of nucleoli. Various types of nuclear inclusions reflect the increased mitotic rate of the neoplastic tissue. Changes of the cellular surface are believed to be associated with the ability of the cells to invade and metastasize. Future investigations will require the use of single doses of potent carcinogens, application of morphometric methods at the ultrastructural level, and acceptance of primates as models for human hepatocarcinogenesis.
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PMID:Ultrastructure of hepatocellular tumors. 22 4

Two malignant fibrous histiocytomas arising primarily in the lung are described. The first was a large tumor of the right lower lobe in a 53-year-old man. The other tumor was found incidentally on routine roentgenograms in a 25-year-old woman and involved the left main pulmonary artery. The lesions could be resected but both patients developed early cerebral metastases. The neoplasms were predominantly fibroblastic, had a characteristic storiform pattern, and included large histiocytes with bizarre nuclei and a vacuolated cytoplasm. The ultrastructure of the cells in the fibroblastic areas was characterized by irregular nuclei and a cytoplasm with a well-developed endoplasmic reticulum and dilated cisternae. Some cells lacked the prominent endoplasmic reticulum of fibroblasts and others were characteristic histiocytes with numerous cytoplasmic lysosomes. The cases appear to be the first reported primary malignant fibrous histiocytomas of the lung.
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PMID:Malignant fibrous histiocytoma of the lung. 22 78

Subcellular fractions of mice thymocytes were used for sensitization of rabbits. The antisera were examined for their immunosuppressive potency in vivo by allogeneic murine tumor metastases system and on skingraft survival and in vitro by leukocyte agglutination tests. The results indicated that the most potent immunosuppressive antisera was that against the second fraction (Fr. 2) of the detergent soluble endoplasmic reticulum fraction from thymocytes.
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PMID:Studies on the effects of heterologous antisera against subcellular thymocyte fraction. 33 45

A quantitative ultrastructural investigation of cancer in mice mammary glands and of its metastases to the lungs was carried out. It was established that in tumors showing no metastatic spreading in experiment the area of membrane surface of the endoplasmic reticulum and the number of bound ribosomes are greater than those in tumor spreading metastases. At the same time the number of ribosomes organized into polysomes is higher in the metastasized tumors. The comparison of the tumors with their metastases revealed differences in the structure of the mitochondrial apparatus: the surface area of cristae is larger in the metastatic foci. The evidence obtained shows that tumors spreading metastases have a lower level of cellular differentiation. The primary and metastatic foci do not exhibit any difference in the level of differentiation.
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PMID:[Relation of the ultrastructural organization of mouse mammary gland cancer to its ability to metastasize]. 43 24

A primary meningeal mesenchymal chondrosarcoma initially resembled an angioblastic meningioma because the typical chondroid islands were not demonstrable. Cartilage was seen only in an intracerebral recurrence and in subsequent extracranial metastases. Ultrastructural examination of noncartilaginous regions of the tumor demonstrated mesenchymal cells with features suggestive of cartilaginous differentiation, viz, scalloped cell membranes, sac-like distension of abundant rough endoplasmic reticulum, and a matrix containing fibrillary and finely granular material. Features of meningeal or pericytic cells were not seen.
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PMID:Primary meningeal mesenchymal chondrosarcoma. 58 58

Ultrastructural studies disclosed that the plaque-like endocardial thickenings in three patients with the carcinoid syndrome were composed of smooth muscle cells embedded in a stroma that was rich in acid mucopolysaccharides, collagen, and microfibrils, but devoid of elastic fibers. The smooth muscle cells contained variable numbers of myofilaments and cisterns of rough surfaced endoplasmic reticulum, and their basement membranes were greatly thickened, reduplicated, and arranged in layers. The endocardial plaques appeared histologically and ultrastructurally similar regardless of their location in the heart. The smooth muscle cells in these plaques appear to have been derived from primitive mesenchymal cells, which normally are present in the subendocardial endothelial space. These observations are interpreted as indicating that the plaques develop as a result of healing of a superficial endocardial injury, which may be initiated by release of bradykinin from hepatic metastases of a carcinoid tumor.
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PMID:The carcinoid endocardial plaque; an ultrastructural study. 93 37

This freeze-fracture study was performed in 3 astrocytomas, 6 glioblastomas, 2 ependymomas, 3 medulloblastomas, 1 cerebellar sarcoma, 3 germinomas, and 1 medulloepithelioma. The number of nuclear pores/mum2 nuclear membrane was not correlated with biological malignancy. Fracture faces A and B were discernible in nuclear, Golgi and rough endoplasmic reticulum (ER), mitochondrial surface, and plasma membranes. Fenestrae were evident in Golgi and ER membranes. The transitional zone of cristae from the inner surface membrane appeared as a circular hole and broken-off neck on faces A and B of the inner surface membrane, respectively. The decrease in number of membrane particles in the plasma membrane seemed to correlate with the frequency of metastases, and, in addition, the membrane particles appeared to cluster in glioblastoma, medulloblastoma, and medulloepithelioma. The gap junctions were abundant in astrocytomas, moderate in number in ependymomas and germinomas, and rare in glioblastomas, cerebellar sarcoma, and medulloepithelioma. Tight junctions were often found in germinomas and medulloepithelioma, and rarely in ependymomas.
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PMID:Freeze-fracture study of human brain tumors. 117 38

The association between testicular tumors/nodules and congenital adrenal hyperplasia (CAH) has been previously reported. From 1960 to 1989, three patients (13 to 18 years old) with long-standing CAH developed testicular masses. Two patients with 21-hydroxylase deficiency were diagnosed in the neonatal period while one other with 11-hydroxylase deficiency was diagnosed at 3 years of age when he presented with sexual precocity. In all three patients, medical compliance was poor. The testicular masses were bilateral in two patients and unilateral in one, measured 1 to 2 cm, and occupied only the upper half of the testicle. Testicular biopsy specimens were obtained after at least 6 months of evidence of compliance with the adrenocorticotrophic hormone (ACTH) suppressive medication and failure of the nodules to regress. On gross examination the masses appeared to be firm yellow brown nodules. Light microscopy showed interlacing strands, cords, and rests of cells resembling interstitial (Leydig) cells but with no Reinke crystalloids. Electronmicroscopy in all patients showed variable amounts of both smooth and rough endoplasmic reticulum, the later with occasional dilated cisternae. Follow-up ranged from 6 months to 6 years. No further surgical treatment has been necessary. There has been no evidence of recurrence, distant metastases, or secondary malignancies during the time of follow-up. These findings suggest that testicular tumors may develop from chronic excessive ACTH stimulation of a putative pluripotential testicular cell, a Leydig cell, or an adrenal cortical rest. Unlike other testicular tumors these do not require orchiectomy as the initial form of therapy.
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PMID:Benign testicular tumors in children with congenital adrenal hyperplasia. 132 Jun 75

The localization of dipeptidyl aminopeptidase IV expressed aberrantly in thyroid carcinoma was studied by immunoelectron microscopy using a monoclonal antibody to the enzyme with special reference to enzyme-histochemical staining of the enzyme. Five thyroid papillary carcinomas were investigated including two lymph-node metastases. All cases showed the dense immunoreaction product on the apical membrane and only traces of the product on lateral membranes, endoplasmic reticulum and nuclear membranes. In one case only, the dense product was observed on basal tubular structures. Analysis, using immunogold labelling on pre-embedded cryosections, revealed that dipeptidyl aminopeptidase IV was localized on the luminal surface of cancer cells. Two different distribution patterns of dipeptidyl aminopeptidase IV activity staining, diffuse and apical patterns, reported previously were thought to be due to different amounts of dipeptidyl aminopeptidase IV in the cytoplasm of cancer cells. This enzyme-histochemical staining method is useful for pathological diagnosis of thyroid tumours and can be applied to clinical materials. The enzyme localization is revealed by the staining pattern.
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PMID:Immunohistochemical localization of dipeptidyl aminopeptidase IV in thyroid papillary carcinoma. 134 35


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