Rhabdomyosarcoma in childhood.

Fifty-four rhabdomyosarcomas in children affected mainly the pelvis and scrotum, 22 cases, head and neck, 19, and limbs and limb girdles, 11. Rhabdomyosarcomas of the female genital tract occurred only in children under 2 years, and those in the lower eyelid presented in the first year of life. A leiomyosarcoma-like appearance, and an undifferentiated small cell sarcoma sometimes mimicking Ewing's tumour, were patterns giving rise to diagnostic difficulty. Many fine gradations from undifferentiated embryonal to almost purely differentiated "pleomorphic" examples, made microscopic classification arbitrary. However, the histological pattern had no bearing on prognosis in children in this series. Of the 46 cases adequately followed, 43 are dead. Two of the 3 long-term survivors had paratesticular tumours.     

Mesenchymal and muscle-specific intermediate filaments (vimentin and desmin) in relation to differentiation in childhood rhabdomyosarcomas

Twenty-one childhood rhabdomyosarcomas were divided into three groups on the basis of cytologic composition. The tumors in group P consisted entirely of primitive mesenchymal cells, whereas those in groups M and W were characterized by the additional presence of numerous round rhabdomyoblasts and strap cells, respectively. The tumors were studied for the universal mesenchymal intermediate filament vimentin, and for the muscle-specific intermediate filament desmin. Vimentin positivity, which tended to be more prominent in primitive tumor cells, was found in all tumors, whereas desmin was found especially in round rhabdomyoblasts and strap cells. Desmin-positive primitive cells were found only in groups M and W, not in group P. It was concluded that the differentiation from primitive mesenchymal cells to morphologically recognizable myogenic tumor cells is accompanied by an increase in desmin positivity and, presumably, a decrease in vimentin positivity. Moreover, the observations suggest the existence of a group of "committed" cells that are morphologically primitive, but desmin-positive. These cells might play an important role in the observed further differentiation of rhabdomyosarcomas under chemotherapy.     

Expression of desmin and myoglobin in rhabdomyosarcomas and in developing skeletal muscle

Immunohistochemical staining for desmin and myoglobin was investigated in 35 rhabdomyosarcomas from young people and in skeletal muscle from 16 human fetuses of known gestational age. Twenty-nine of the rhabdomyosarcomas expressed desmin but six undifferentiated or poorly-differentiated tumours were desmin negative. Of the desmin positive cases, most undifferentiated or poorly-differentiated sarcomas expressed desmin alone (12/35). Tumours with increasing rhabdomyoblastomic differentiation co-expressed myoglobin (9/35) and well-differentiated examples also contained cross-striations (7/35). Skeletal muscle from fetuses aged 8 weeks or less consisted mainly of primitive desmin negative round cells. As the cells began to differentiate they quickly expressed desmin and, at approximately 10 weeks, myoglobin was expressed and cross-striations were seen. The combined results strengthen the view that desmin (within a strictly defined context of round cell tumours in young people) is a reliable marker for rhabdomyoblastic differentiation. Support is also given to the notion that very primitive rhabdomyosarcomas may be desmin-negative, although the difficulties of establishing firm diagnoses for some of these tumours is emphasized.     

Immunohistochemistry of desmin and vimentin in smooth muscle tumors of the digestive tract

The expression of desmin and vimentin in 35 "smooth muscle tumors" of the digestive tract was investigated using formalin-fixed and paraffin-embedded materials and the indirect immunoperoxidase method. Fourteen of 15 esophageal tumors and two of 15 gastric tumors were categorized as benign leiomyoma with low cellularity, and immunohistochemically were desmin-positive and vimentin-negative as were normal muscle layers of the digestive tract. The remaining tumors showed moderate to high cellularity: Six tumors seemed to be malignant on the basis of frequent mitosis and/or nuclear atypia, while 11 were considered to be of borderline malignancy. This cellular tumor group exhibited consistent vimentin immunoreactivity, but desmin was negative or only weakly and/or focally positive. S-100 protein was fundamentally negative in these tumors. The pitfalls of studying desmin immunohistochemistry as a routine diagnostic tool in surgical pathology are discussed.     

Immunofluorescent localization of desmin and vimentin in developing cardiac muscle of Syrian hamster

The distributions of desmin and vimentin were examined in frozen sections of cardiac muscle from embryonic, newborn, and adult Syrian hamster by using immunofluorescent methods. Frozen sections of newborn and adult skeletal muscle were used for comparison. Cardiac myocytes from day 9 in utero embryos already show a clear association of desmin with the sarcomeric myofibrils. In newborn hearts, desmin is localized in the myofibrillar Z-line areas as well as in the peripheral cytoplasm of the cell. Three days after birth, desmin is associated with the intercalated discs. Thus, in adult cardiac muscle, desmin is present in both Z-bands and intercalated discs. Skeletal muscle of newborn and adult hamster also contains desmin associated with the Z-lines of myofibrils. Vimentin is associated with the myofibrils of day 9 in utero cardiac muscle cells. The protein remains associated with the myofibrillar Z-lines in the newborns and adults. No detectable staining for vimentin was observed in newborn or adult hamster skeletal muscle. The existence of vimentin as well as desmin in differentiated cardiac muscle may be a consequence of the somewhat more epithelial-like nature of cardiac cells as compared to skeletal muscle syncitia.     

Intermediate-sized filament proteins (prekeratin,vimentin, desmin) in the normal parotid gland and parotid gland tumours

Summary Antibodies to different intermediate-sized filament proteins can distinguish cells and tissues of epithelial, mesenchymal, muscle, astrocytic and neural origin. Antibodies to prekeratin, vimentin and desmin have been used to distinguish cells of epithelial, mesenchymal and muscle origin in the normal human parotid gland, and in addition to study some common tumors of this gland. Prekeratin-positive and vimentin-positive cells are found among the tumor cells in the pleomorphic adenomas. In contrast the tumor cells of the mucoepidermoid tumors and squamous cell carcinomas are prekeratin-positive but vimentin-negative.Supported by the Deutsche Forschungsgemeinschaft (Ca 93/1-1) and by the Hamburger Stiftung zur Förderung der Krebsbekämpfung     

An immunohistological study of human lymphoma.

In this study the problems encountered in staining immunoglobulin (Ig) in sections of paraffin-embedded human lymphoma samples have been investigated. It was found that the "masking' of cytoplasmic Ig, which occurs when tissues are fixed in formol saline (the fixative employed in most previous studies), can be avoided by the use of mercury-based fixatives. When non-Hodgkin's lymphoma samples fixed in this way were studied it was found that cytoplasmic Ig labelling of both lymphoid and histiocytic cells is often attributable to non-specific uptake of serum proteins. This phenomenon probably accounts for a number of published anomalous immunoperoxidase staining results in human lymphoma (e.g. the presence of both kappa and lambda chains in the same neoplastic cell). Double immunoenzymatic labelling (using alkaline phosphatase and peroxidase) proved valuable in the elucidation of this phenomenon. When staining due to absorbed Ig was discounted it was possible to demonstrate monoclonal Ig labelling in seven out of sixteen cases of non-Hodgkin's lymphoma. In each case IgM was found in association with a single light chain type and these results were in agreement with those obtained by direct immunofluorescent labelling of cryostat sections. In a further case u chains without associated light chains were demonstrated by immunoperoxidase staining. Seven cases of Hodgkin's disease were studied by immunoenzymatic techniques. Although IgG was frequently found in Reed-Sternberg and Hodgkin's cells its presence was not attributable to non-specific uptake of serum protein since albumin was absent or only present in small amounts. These findings are in support of the macrophage origin of these cells.     

Immunomorphologic diagnosis of early myocardial necrosis using monoclonal antibodies to desmin and vimentin]

Apart from monoclonal antibodies against cytoskeleton proteins, polyclonal antibodies to gamma-globulin and immunoglobulin G were used. Mosaicism of myocardial damage was observed: the intermittence of acute necrosis foci with areas of ischemia and normal myocardium. Desmin may serve a marker of early necrosis in the myocardium.     

Gene and protein expressions of vimentin and desmin during embryonic development of the mylohyoid muscle

Meckel's cartilage is known to be involved in formation of the prenatal mandible. However, the relationship between Meckel's cartilage and the embryonic mylohyoid muscle during growth and development has been investigated only rarely. This study examined the expression of intermediate filaments in Meckel's cartilage and the embryonic mylohyoid muscle in fetal mice during morphological development. Specimens of E12-16 ICR mice sectioned in the frontal direction were subjected to immunohistochemistry for vimentin and desmin. Hematoxylin and eosin sections showed that the immature mylohyoid muscle began to grow along Meckel's cartilage during fetal development. Weak vimentin expression was detected in the mylohyoid muscle and surrounding tissues at E12. Desmin expression was detected specifically in the mylohyoid, and strong expression was evident after E13, and increased with age. It was inferred that the mylohyoid muscle is one the tissues developing from Meckel's cartilage, the latter exerting a continuous influence on the growth of the former. In the early stage, the surrounding mesenchymal tissues expressing vimentin formed a scaffold for the developing mylohyoid muscle. Muscle attachment at E13 showed steady desmin expression, which continued until maturity. This study suggested the possibility that Meckel's cartilage has an influence not only on the mandibular bone, but also on the development of the mylohyoid muscle attached to the mandibular bone. Furthermore, it revealed a stage of the developmental process of the mylohyoid muscle in which the expression of vimentin, which is a common protein in the surrounding tissue such as muscle and bone, induces the morphological formation of the mylohyoid muscle, cooperating with the surrounding structures.     

Human monoclonal antibody derived from an autoimmune thrombocytopenic purpura patient, recognizing an intermediate filament's determinant common to vimentin and desmin.

Human monoclonal antibody (mAb) technology has been helpful in identifying autoantibodies that are involved in various autoimmune disorders. We report here the results of such an attempt to immortalize antibody-forming cells from spleen of an autoimmune thrombocytopenic purpura (ATP) patient and characterize the resulting mAb. The human mAb we derived, denoted (4G9), binds to the cytoskeletal network. Using immunofluorescence analyses of permeabilized and fixed cell lines and tissues, the 4G9 mAb was shown to be anti-vimentin specific by virtue of its intracellular staining pattern, decoration of cell lines of mesenchymal (but not epithelial) origin, and by the fact that polyclonal anti-vimentin (and not anti-actin, prekeratin, tubulin or vinculin) antibodies inhibited its binding to intermediate filaments of a fibroblastoid cell line. The presence of vimentin in platelets was also confirmed in the present study by immunoblotting of platelet extract using murine anti-vimentin mAb. Interestingly, in addition to vimentin the 4G9 mAb decorated intermediate filaments in desmin-expressing muscular cells, suggesting that the 4G9 epitope is most likely located within the homologous sequences that are known to be shared between vimentin and desmin.     

Cushing syndrome-associated pheochromocytoma and adrenal carcinoma. An immunohistological investigation.

Seven adrenal carcinomas and seventeen pheochromocytomas (PHs), two of which were clinically associated with a Cushing's syndrome and one associated with multiple endocrine neoplasia Type II (MEN-II), were investigated immunohistologically with a panel of antibodies against intermediate filament proteins, a proliferation-associated nuclear antigen (Ki-67), neuroendocrine tumor markers, and different hormones on paraffin-embedded tissue sections and, from 19 cases, also on frozen tissue sections. Synaptophysin proved to be the most reliable tumor cell marker on both snap-frozen and paraffin-embedded tissue but, like antibodies against NSE, yielded unspecific stainings in the carcinomas. The two Cushing-associated pheochromocytomas (CaPH) showed the same immunohistological profile as the other PHs, except one chromogranin-negative tumor. Five PHs showed weak reactivity for calcitonin, one for serotonin, and two for a-HCG in small amounts. All PHs lacked other hormone expression, including ACTH. The average growth fraction was small (2.2%) in 13 cases, but 80% of the tumor cells were proliferating in one case of CaPH. Adrenal carcinomas showed only weak or no expression of keratin in one case, a homogenous or droplet, non-filamentous cytoplasmic staining with antibodies against neurofilament in frozen tissue section, and they were completely chromogranin-negative. The average growth fraction was 7.6% in 5 cases.     

Granular cell tumours revisited. An immunohistological and ultrastructural study

Twenty-five granular cell tumours were stained with a panel of antibodies to histiocytic, muscle, neural, neural crest, epithelial and endothelial markers. Electron microscopy was also performed in six cases. Twenty-four of the cases were similar morphologically and immunocytochemically. One case with features of an endothelial origin is described. The present study strongly supports the viewpoint that granular cell tumours are a distinct entity rather than being the common appearance of a group of lesions of differing histogenesis. Origin from a neural crest-derived peripheral nerve-related cell is favoured.     

An immunohistological comparison of primary lung carcinosarcoma and sarcoma.

We wished to assess the antigenic expression of primary lung tumors diagnosed as either carcinosarcoma or sarcoma in order to determine whether this information would be useful in distinguishing the two. We therefore immunohistochemically analyzed six pulmonary carcinosarcomas and five primary lung sarcomas for the presence of carcinoembryonic antigen (CEA), S100 protein, cytokeratin and vimentin using commercially available monoclonal and polyclonal antibodies on formalin fixed tissues. Six of six carcinosarcomas stained positively for cytokeratin while none of the sarcomas stained. In three carcinosarcomas both the carcinomatous and sarcomatous areas were positive while in three only the carcinomatous areas were positive. CEA staining was present in five carcinosarcomas and absent in all the sarcomas. CEA positivity was strong and not confined to those tumors with obvious gland formation. Staining for S100 protein was positive in two carcinosarcomas but only in those areas showing chondroid differentiation. Immunohistochemical staining for vimentin using two different monoclonal antibodies gave inconsistent results. We conclude that in differentiating between a carcinosarcoma and a sarcoma of the lung, immunohistochemical staining for both cytokeratin and CEA are useful with cytokeratin marginally preferable. The data indicate that carcinosarcoma of the lung, like that of the upper aerodigestive tract, expresses antigens suggesting both epithelial and mesenchymal differentiation.     

The intermediate filament proteins of rabbit vascular smooth muscle: immunofluorescent studies of desmin and vimentin

Summary The localization of desmin and vimentin in rabbit vascular smooth muscle was studied using the fluorescent antibody technique. Desmin and vimentin were present in the smooth muscle cells of the portal anterior mesenteric vein, renal vein and renal artery. All endothelial cells and the smooth muscle cells of the abdominal aorta and main pulmonary artery contained only vimentin. The results suggest that desmin and vimentin are differentially distributed in rabbit vascular smooth muscle and that both may occur in a single blood vessel.