RESUMO
The zebrafish (Danio rerio) has been successfully used to discover hundreds of genes involved in development and organogenesis. To address the potential of zebrafish as a cancer model, it is important to determine the susceptibility of zebrafish to tumors. Germ line mutations are most commonly induced for zebrafish mutant screens by exposing adult male zebrafish to the alkylating agent, ethylnitrosourea (ENU). To determine whether ENU induces tumors, we compared the incidence of tumors in ENU-treated fish with untreated controls. Interestingly, 18 of 18 (100%) fish mutagenized with either 2.5 or 3.0 mM ENU developed epidermal papillomas, which numbered 1 to 22 per fish, within 1 year of treatment. The induced epidermal lesions included epidermal hyperplasia, flat papillomas (0.2 to 1.2 mm), and pedunculated papillomas (1.2 to 8 mm in greatest dimension), but no skin cancers. Angiogenesis was evident in papillomas larger than approximately 1 mm. All but two papillomas contained the three cell types (keratinocytes, club, and mucous cells) of normal zebrafish epidermis; histologic variants lacked either club cells or mucous cells. Two cavernous hemangiomas and a single malignant peripheral nerve sheath tumor were also found in the treated fish. None of five untreated controls developed tumors. These studies establish the feasibility of the zebrafish as an experimental model for the study of skin tumors.
Assuntos
Carcinógenos/toxicidade , Etilnitrosoureia/toxicidade , Papiloma/induzido quimicamente , Neoplasias Cutâneas/induzido quimicamente , Animais , Mutação em Linhagem Germinativa , Masculino , Mutagênicos/toxicidade , Neovascularização Patológica , Papiloma/irrigação sanguínea , Papiloma/genética , Neoplasias Cutâneas/irrigação sanguínea , Neoplasias Cutâneas/genética , Peixe-ZebraRESUMO
Perineurioma is a rare, probably benign peripheral nerve sheath neoplasm. Perineurial cell origin is most efficiently demonstrated immunohistochemically by positivity for epithelial membrane antigen and negativity for S-100 protein and Leu 7.
Assuntos
Perna (Membro)/inervação , Neoplasias de Bainha Neural , Neoplasias do Sistema Nervoso Periférico , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias de Bainha Neural/patologia , Neoplasias do Sistema Nervoso Periférico/patologiaRESUMO
The cellular manifestations of extrauterine cancer have been well documented. While finding metastatic carcinoma in gynecologic specimens should not be unexpected, descriptions of certain types of neoplasms are not well represented in the cytology literature. We describe the clinical, cytopathologic and histologic features of a case of signet ring cell breast carcinoma metastatic to the uterine cervix. Signet ring cell breast carcinoma is a rare neoplasm, and its possible histogenesis is discussed.
