Neoplastic Endothelial Cells Research Articles

Hobnail hemangioma ("targetoid hemosiderotic hemangioma"): clinicopathologic and immunohistochemical analysis of 62 cases.

Hobnail hemangioma, also known as "targetoid hemosiderotic hemangioma", represents a distinctive, benign vascular tumor, characterized histologically by a biphasic growth pattern of dilated vascular structures in the superficial dermis lined by prominent hobnail endothelial cells, and collagen dissecting, rather narrow neoplastic vessels in deeper parts of the lesion. We analyzed the clinicopathologic and immunohistochemical features in a series of 62 cases. Patient age range was 6-72 years (median: 32 years); 34 patients were male and 25 female. Clinically, a broad variation of diagnoses ranging from hemangioma to dermal melanocytic nevus and fibrous histiocytoma was suggested. Nineteen tumors arose in the lower and 13 in the upper extremities, 12 on the back, 8 in the buttock and hip region, and one case on the chest wall. Follow-up information on 35 patients (range from 1 to 4 years; mean: 1.5 years) revealed no local recurrence nor systemic metastasis. All neoplasms were located in the dermis and showed a broad morphologic spectrum in dependence of the age of the lesions. In addition to lesions resembling cavernous lymphangioma or lymphangioma circumscriptum, neoplasms were seen with morphologic features reminiscent to retiform hemangioendothelioma, progressive lymphangioma and so-called Dabska's tumor. Immunohistochemistry performed in 28 cases showed positive staining of tumor cells for CD31 in all cases tested, whereas only 3 out of 28 cases stained completely positive for CD34. In addition 4 out of 8 cases stained positively for vascular endothelial growth factor receptor-3 (VEGFR-3). Neoplastic endothelial cells were surrounded by actin-positive pericytes in only 7 out of 27 cases tested. Hobnail hemangioma occurs more frequently in male patients and arises commonly in the extremities and the trunk. Histologic and immunohistochemcial features suggest a lymphatic line of differentiation for this distinctive vascular neoplasm.

A human vascular endothelial cell model to study angiogenesis and tumorigenesis.

Endothelial cell biology has recently been the subject of considerable interest in thrombosis and cancer research. However, the successful establishment of immortalized human endothelial cells which retain differentiated cell characteristics has been rare. We have successfully established immortalized human umbilical vein endothelial cells (HUVECs) by human papilloma virus (HPV)-16 E6-E7. HPV-16 E6, E7 and E6-E7 were successfully introduced into HUVEC cells. Both E6 and E7 cultures had an extended lifespan but eventually underwent senescence. E6-E7 cultures 4-5-2G, however, acquired an indefinite lifespan in culture but did not undergo malignant conversion. Telomerase activity was not detected in either E6 or E7 cultures; however, telomerase was detected in E6-E7 4-5-2G cells. The cells exhibited a 'cobblestone' morphology and developed a capillary-like tube structure upon reaching confluence. The 4-5-2G line expressed Factor VIII related antigen and took up DiI-Ac-LDL as markers of endothelial origin. The line expressed integrin subunits (alpha(v)beta3, alph(v)beta5, beta1, alpha2, alpha3, beta4 and alpha6) consistent with an endothelial origin. The higher passage of 4-5-2G line showed a similar intensity of integrin immunostaining to that of primary HUVECS. Subsequent infection of these immortal cells with the Kirsten murine sarcoma virus which contains an activated K-ras oncogene induced morphological transformation that led to the acquisition of invasion capability and neoplastic properties. Telomerase was also detected in the tumorigenic v-Ki-ras transformed cell line. These cell lines should be useful for studies of the molecular mechanisms underlying normal and neoplastic endothelial cell proliferation and migration, and might also provide an in vitro model for development of pharmacologic and gene therapy for cardiovascular thrombosis and cancer.

Communications: Metastatic Gill Lesions Secondary to Cardiac Hemangioendotheliosarcomas in the Teleost Fish Mangrove Rivulus

Abstract Gill neoplasms have been infrequently described for teleost fishes. Nine of 51 cases of primary cardiac endothelial cell neoplasms of a teleost fish species, mangrove rivulus Rivulus marmoratus, also possessed endothelial cell neoplasms in their gills. These neoplasms occurred in the afferent arterioles of the gill filaments. They were made up of round cells or spindle cells that had nuclei similar to typical endothelial cell nuclei. The large gill neoplasms, with more anaplastic cells, penetrated the walls of the gill arterioles and invaded adjacent gill tissues. Supporting evidence for the metastatic nature of these gill neoplasms includes the following: (1) they were secondary in timing, numbers, and size to the advanced sarcomas of the heart; (2) cell phenotypes of both gill and cardiac neoplasms were similar in cytoplasmic and nuclear features; (3) the cardiac neoplasms appeared to be shedding neoplastic endothelial cells into the lumen of the bulbus arteriosus with a direct route via the ci...

Immunohistochemistry in tumour diagnosis.

Immunohistochemistry has become an everyday tool in diagnostic pathology to increase the accuracy in tumour typing. The most important recent developments include availability of antibodies to leukocyte CD-antigens to nearly comprehensive lymphoma typing in paraffin sections, use of certain leukocyte antigens in typing of solid tumours, e.g. neoplastic endothelial cells (CD31 and CD34) and neural and neuroendocrine cells (CD56, CD57). Also, antibodies selective to individual keratin polypeptides promise to be helpful in the subtyping of carcinomas. Antibodies to nuclear proliferation antigens have already proven helpful in the characterization of tumour cell proliferation. Technical optimization, using enzymatic and non-enzymatic antigen retrieval modalities, is also important.

Epitopic heterogeneity of the CD36 antigen expressed by normal and neoplastic endothelial cells. An immunohistochemical study with a novel monoclonal antibody 8C9.

Phenotypic and functional heterogeneity of endothelial cells (ECs) is being recognized with increasing frequency. Here we report a novel murine monoclonal antibody (MoAb), named 8C9, that detects a unique epitope on the leukocyte differentiation antigen CD36 (platelet glycoprotein IV or IIIb) expressed by both normal and neoplastic ECs. In immunohistochemical and flow-cytometric studies, 8C9-immunoreactivity was detected on capillary ECs, adipocytes, monocytes, platelets and a human monocytoid cell line U-937, which are known to express the CD36 antigen. Blocking experiments using U-937 cells and studies on cryostat sections revealed that a murine MoAb OKM5, which detects the CD36 antigen, blocked the binding of 8C9 to its antigen. Immunoblot analysis showed that 8C9 bound to a 97-kDa membrane protein expressed by U-937 cells treated with phorbol ester. These results indicate that 8C9 detects the CD36 antigen. However, the findings that some OKM5-positive normal ECs in the liver, spleen and lymph nodes as well as neoplastic ECs in a cutaneous angiosarcoma did not react with 8C9, together with the fact that the CD36 antigen does not form a complex or associate with other proteins, suggest epitopic heterogeneity of the CD36 antigen expressed by these tissues.

Immunocytochemical evidence of lymphocytic derivation of neoplastic cells in malignant angioendotheliomatosis

Neoplastic angioendotheliomatosis is a rare disorder usually characterized by primarily cutaneous or neurological symptoms. Approximately 40 cases of malignant angioendotheliomatosis with primary central nervous system (CNS) symptoms have been reported. Some investigators have postulated a hematopoietic origin for this neoplasm. Most of the literature, however, has perpetuated the idea that the often bizarre symptoms seen with this entity result from neoplastic endothelial cell proliferation within the small vessels of affected organs, including the brain and spinal cord. This report describes the immunohistochemical examination and confirmation of the cell of origin of this neoplasm based on five previously unpublished cases of malignant angioendotheliomatosis with primarily CNS symptoms. It includes the first documentation of a T-cell lymphoma presenting as malignant angioendotheliomatosis. All cases include autopsy findings, and in four cases the diagnosis was made postmortem. One case was proven by stereotactic biopsy, but the patient succumbed as a result of severe intracranial bleeding that occurred at the time of biopsy. Tissues were studied with avidin-biotin peroxidase immunohistochemical techniques using a panel of monoclonal antibodies directed against the leukocyte common antigen, LN-1, LN-2, and anti-Factor VIII, and also using Ulex europaeus agglutinin 1. Based on the results obtained, the authors conclude that the proliferative cells seen within the vessel lumina are of lymphocytic origin and agree that the condition should more properly be designated intravascular lymphomatosis. The therapeutic implications of this conclusion point to the possible administration of chemotherapy and radiotherapy in an effort to achieve remissions in an otherwise relentlessly progressive neurological disorder.

Phenotypic Characterization of Normal and Neoplastic Canine Endothelial Cells by Lectin Histochemistry

Cell surface glycoconjugate expression of endothelial cells in canine cutaneous hemangiomas and hemangiosarcomas was compared to normal cutaneous endothelial cells using eight different lectins (with and without neuraminidase pretreatment) in an indirect immunoperoxidase technique. Direct comparison of lectin binding pattern of neoplastic endothelial cells with adjacent normal endothelial cells revealed minor changes in the binding intensity of several lectins (enhanced: Wheat germ agglutinin [WGA]; reduced: Griffonia simplicifolia-I [GS-I], Ricinus communis agglutinin-I [RCA-I], Soybean agglutinin after neuraminidase pretreatment [Neu-SBA], and Wheat germ agglutinin after neuraminidase treatment [Neu-WGA]). Neoplastic endothelial cells in some tumors exhibited varying binding of Ulex europaeus agglutinin-I (UEA-I; not binding to normal canine endothelial cells) and no Soybean agglutinin (SBA) binding (variably binding to normal endothelial cells in small cutaneous vessels). Lectin binding of neoplastic cells was rather heterogenous within one tumor compared to the uniform binding pattern of normal endothelial cells. These lectin binding studies demonstrate the phenotypic heterogeneity of neoplastic endothelial cells, indicating changes of cell surface glycosylation during neoplastic transformation.

Epithelioid hemangioendothelioma of the liver: An ultrastructural study

Epithelioid hemangioendotheliomas are uncommon vascular tumors, mainly observed in lung and soft tissues. Liver involvement is infrequent and, in contrast to the extrahepatic localizations of the tumor, has not been subjected to detailed ultrastructural analysis. This prompted us to report the results of the ultrastructural study of three cases of epithelioid hemangioendothelioma of the liver. Neoplastic proliferation was heterogenous. Most of neoplastic cells presented features suggestive of endothelial differentiation, including presence of Weibel-Palade bodies and evidence of vasoformative properties demonstrated by formation of both intra- and extracellular vascular channels resembling the normal structures successively observed during embryogenesis and tissue regeneration. A minor cell population, unreported so far, exhibited ultrastructural characters resembling those of pericytes and presented organoid relationship to neoplastic endothelial cells. Tumor spreading along sinusoids induced pseudopeliotic dilatations and led to a progressive disruption of normal liver architecture. In conclusion, the three cases of hepatic epithelioid hemangioendothelioma examined in this work assume many organoid features mimicking the successive steps of normal angioformation and indicative of a high degree of morphological differentiation.

Ultrastructural and Immunocytochemical Observations on Angiosarcomas

Forty-seven angiosarcomas have been studied by light and electron microscopy. Neoplastic endothelial cells do not consistently display specific ultrastructural features, but certain aspects of the fine structure of the cells and their arrangement can be useful to establish or confirm the diagnosis. Experience with the common endothelial cell markers as diagnostic aids is briefly reviewed.

Factor VIII-related antigen in canine endothelial neoplasms: an immunohistochemical study.

Canine vascular tumors (47 hemangiomas, 36 hemangiosarcomas) were investigated for the endothelial cell marker factor VIII-related antigen (F VIII RAg). The primary antibody was a commercial rabbit anti-human (r/h) F VIII RAg antiserum. All (100%) hemangiomas and 32 (89%) of 36 hemangiosarcomas stained for F VIII RAg. One hemangiosarcoma (3%) was negative, and three tumors (8%) were equivocal in staining. Rarely, the interpretation of stained immature endothelial cells was difficult. The r/h F VIII RAg antibody was a positive marker of normal, reactive, and neoplastic endothelial cells in the dog.

Neoplastic transformation of the rat visceral yolk sac by polyoma virus

The transforming activity of polyoma virus was verified in vitro in organ cultures of 12-day old rat visceral yolk sacs and embryos. Organ cultures of 18-day old fetal organs were also included. The transforming capacity of the virus was found to be restricted to the endothelial cells of the rat visceral yolk sac. The neoplastic endothelial cells are readily transplantable and possess the polyoma tumor-specific transplantation antigens (TSTA).

Erythrophagocytosis in Kaposi's sarcoma in acquired immune deficiency syndrome.

The ultrastructural morphology of Kaposi's sarcoma of the oral mucosa in patients with acquired immune deficiency syndrome (AIDS) was examined electron-microscopically. Neoplastic spindle cells and vascular endothelial tumor cells are frequently involved in the phagocytosis of extravasated erythrocytes. Pericytes, fibroblasts, macrophages and other phagocytic cells of the tumor stroma also participate in this process. Erythrocytes are also phagocytized by some of the keratinocytes belonging to the intact surface epithelium covering the Kaposi's sarcoma lesion. Both the phenomenon of erythrophagocytosis and the presence of tubuloreticular structures in the cytoplasm of Kaposi's sarcoma cells in patients with AIDS seem to be prominent ultrastructural markers and thus of diagnostic value.

Gliosarcomas: histological, immunohistochemical, ultrastructural, and tissue culture studies.

Thirty-nine cases of gliosarcomas, two initiating as fibrosarcomas, 25 as mixed gliomas and sarcomas, and 12 as anaplastic gliomas with secondary sarcomas, were studied by light microscopy, immunohistochemistry, using GFAP, factor VIII/RAg, and Ulex europaeus I agglutinin (UEA I), electron microscopy and tissue culture. GFAP was found variably positive in the glial areas; F VIII/RAg and UEA I, markers of both normal and neoplastic endothelial cells and their derivatives, were found in vessels of both gliomatous and sarcomatous parts of GS, less intensive in hyperplastic glomeruloid structures and, with decreasing intensity, in adjacent fibrosarcomatous areas, while UEA I, giving stronger reaction than F VIII/RAg, was occasionally demonstrated in sarcomatous cells. In vitro studies confirmed previous data of a separate growth of glial and mesenchymal cells with a divergent migratory speed. Electron microscopy demonstrated the frequent close admixture of glial and mesenchymal tumor cells, which showed the feature of either fibrosarcoma or angiosarcoma. The frequent resemblance of the latter with endothelial cells was supported by the occasional demonstration of Weibel-Palade-like bodies in both vascular endothelial and adjacent sarcomatous cells. These observations confirm the hypothesis that at least part of the sarcomatous components in many GS originate from vascular endothelial proliferation and obviously represent the final stage of a process starting with the endothelial hyperplasia in anaplastic gliomas.

Distribution of endothelial and basement membrane markers in angiogenic tumors of the nervous system.

The distribution of two endothelial cell markers Factor-VIII-related antigen and Ulex europaeus agglutinin was examined by immunoperoxidase and immunofluorescence techniques in paraffin-embedded specimens representing the three main types of angiogenic neoplasms of the nervous system, hemangioblastoma, hemangioendothelioma and hemangiopericytoma. In addition, the distribution of the basement membrane (BM) marker, laminin, was studied in the same tumors. It was found that Ulex europaeus agglutinin was a more sensitive marker of neoplastic endothelial cells than Factor-VIII-related antigen. Both markers only stained endothelial cells, while the tumor cells of hemangiopericytomas and the stromal cells of hemangioblastomas remained unstained. These findings do not support the view that the stromal cells of hemangioblastomas are derived from endothelial cells. With antiserum to laminin a typical staining pattern could be noticed in each tumor, showing the architectural relationships of the cells very clearly. In all three tumor types laminin was only found in the BM of the vessels, not in the interstices of the neoplastic cells outside vessel lumina. Therefore, the reticulin network previously found between the individual cells of hemangiopericytomas does not correspond to BM. It is concluded that both Ulex europaeus agglutinin and laminin antisera could be valuable new aids for the diagnosis of the three tumor types.

Angio-proliferative lesions in a homosexual boar with features resembling Kaposi's sarcoma.

Clinical, biopsy and necropsy studies of a homosexual boar revealed angio-proliferative lesions in the skin of the thigh, scrotum and the inguinal lymph node. Angiofibromas were identified in the dermis and subcutis of the thorax and mandible. The avidin-biotin-peroxidase complex technique demonstrated Factor VIII-related antigen as a marker for the neoplastic endothelial cells of the tumors. This boar also showed weight loss and lymphopenia. Explants of tumors were maintained in cultures for 22 passages and cultured cells produced tumors when injected subcutaneously into nude mice. No viral antigen was detected in the cultured tumor cells. Similarities and differences between the lesions in the boar and human Kaposi's sarcoma are discussed.

Scanning electron‐microscopic study of the surface characteristics of neoplastic endo‐thelial cells of blood vessels

The morphological surface characteristics of neoplastic endothelial cells of blood vessels induced by oral administration of 1,2-dimethylhydrazine dihydrochloride in mice were studied by scanning electron microscopy. The interconnecting vascular channels were lined by malignant endothelial cells which formed bridges, cord-like structures and had extended cytoplasmic processes which made the network more intricate. The endothelial cells were often in close approximation to each other and exhibited irregular growth patterns and orientation. The cell surface displayed a rugged, terrace-like microcontour of elevations, depressions, blebs and nodular structures. These findings correlate with the earlier morphological observation obtained by transmission electron microscopy.

1,1-Dimethylhydrazine (unsymmetrical) carcinogenesis in mice. Light microscopic and ultrastructural studies on neoplastic blood vessels.

Administration of 0.01% unsymmet,rical 1,1-dimethylhydrazine in the drinking water of 5-week-old randombred Swiss mice throughout their lifetime induced tumors of blood vessels, lung, kidney, and liver. The incidences of tumors in these 4 tissues were: 79, 71, 10, and 6%, while in the untreated controls they were 2, 11, 0, and 0%, respectively. The vascular tumors occurred in the liver, muscle, heart, lung, and fat. Macroscopic, light and electron microscopic, and histochemical examinations of the vascular lesions revealed a morphology typical of angiosarcomas. The gross and histologic involvement of the tissues with the tumors is described and illustrated. The ultrastructure of hemorrhagic areas, angiosarcoma with its components, and the neoplastic endothelial cells and their associated structures and membranes are shown in detail. The findings of this study prove unequivocally the carcinogenicity of this important rocket propellent and provide further evidence for a possible relationship between the chemical structure of hydrazine derivatives and tumor development at specific organ site.