晕痣和痣细胞痣OKT6阳性细胞的免疫组化观察

对晕痣和痣细胞痣进行了 OKT6阳性细胞的免疫组化观察 ,结果表明晕痣表皮内 OKT6阳性细胞数显著多于痣细胞痣 ,提示 OKT6阳性细胞可能在晕痣的自身免疫发病机制中起着一定作用     

Tangential excision of nevocellular nevus on the face

BACKGROUND: Tangential excision (shaving) is an effective surgical technique for the excision of nevocellular nevi on the trunk, limbs, and scalp. There are few studies on the application of this technique to lesions on the face. AIMS: To demonstrate the technique of tangential excision for the removal of nevocellular nevi on the face and to evaluate the cosmetic results, recurrence index, and possible complications. METHODS: Two hundred and fifteen patients with multiple nevocellular nevi on different aesthetic units of the face (total of 225 lesions) were selected. All the lesions were removed by tangential excision. The patients returned for postsurgical evaluation at 30, 60, and 90 days. RESULTS: The results were evaluated in relation to the skin type, sex, age, and histologic type of the lesions. An excellent result was achieved in 90.7%, good in 8.4% and poor in 0.9%, with a low index of complications. For comparison, the face was divided into seven aesthetic units. CONCLUSION: Tangential excision is an alternative surgical technique for the treatment of nevi. It is simple, fast, and efficient, has low risks and low cost for the patient, and yields excellent results when used for cosmetic purposes.     

E-cadherin expression in the subepithelial nevus cells of the giant congenital nevocellular nevi (GCNN) correlates with their migration ability in vitro

BACKGROUND: Giant congenital nevocellular nevi (GCNN) are histologically characterized by the broad distribution of nevus cells in the epidermis and dermis. OBJECTIVE: To characterize E-cadherin in GCNN and define its role in nevic cell migrations. METHODS: Twenty-four cases were immunohistochemically examined and in five cases cells were isolated for primary culture for migration assays. RESULTS: The nevus cells in the superficial region showed the immunoreactivity of E-cadherin in a membranous pattern, but those in the deep part of dermis had little immunoreactivity. Ultra-structural analysis of the superficial nevus cells revealed that E-cadherin immunodeposits in the fibrillar processes around the cell body in a spotted pattern. This distribution pattern is quite different from that in the adherens junction of skin squamous epithelial cells. Boyden chamber experiments were performed using primary cultures of intradermal nevus cells. EDTA pretreatment reduced cell migration to the E-cadherin positive side when the E-cadherin positive population was relatively large in the primary cultures. CONCLUSIONS: These results indicate that E-cadherin in the nevus cells may affect nevus cell motility rather than intercellular attachment.     

Growth and phenotypic characteristics of human nevus cells in culture

Nevus cells were isolated from the three cutaneous components, epidermis, basal layer, and dermis, of nonmalignant pigmented lesions and were cultured separately in the presence or absence of the phorbol ester 12-0-tetradecanoyl phorbol-13-acetate in medium that supports the rapid proliferation of melanocytic cells. The separation procedure used provided cultures that were essentially free from normal melanocytes (dermis) or fibroblasts (epidermis). In short term culture, nevus cells of all skin compartments expressed markers associated with differentiated melanocytes, such as presence of premelanosomes and melanosomes and elevated tyrosinase levels. Nevus cells also expressed melanoma-associated antigens, such as NGF-receptor, transferrin-related p97, proteoglycan, and HLA-DR as detected with monoclonal antibodies. After several subpassages, cells showed a decreased expression of melanoma-associated antigens, decreased tyrrosinase levels, and melanosomes could no longer be detected. Morphologically, these cells were similar to fibroblasts. The disappearance of melanoma-associated cell surface antigens was concomitant with the appearance of a melanocyte-associated 145 kd protein that might serve as a marker of fibroblast-like differentiation in nevus cells and normal melanocytes. Nevus cell cultures grown in the presence of 12-0-tetradecanoyl phorbol-13-acetate maintained a stable differentiated phenotype throughout their lifespan. As reported earlier, nevus cells in culture, irrespective of the presence or absence of 12-0-tetradecanoyl phorbol-13-acetate, have a finite lifespan in vitro, grow anchorage-independent in soft agar, but do not form tumors when xenografted to nude mice. These studies demonstrate that nevus cells isolated from the epidermal, basal layer, and dermal components of lesional skin can serve as models to characterize the initial steps of tumor progression in a human cell system.     

A comparative study of fluorescence in malignant melanoma and nevocellular nevus using a fluorescence microscope and formalin-fixed specimens

Fluorescence in malignant melanoma cells was investigated. The specimens from 18 cases of malignant melanoma and 26 cases of nevocellular nevus, which were fixed with formalin and embedded in paraffin wax, were studied by the fluorescence microscopic method. On the fluorescence microscope, the malignant melanoma cells emitted intense fluorescence from the cytoplasm. The nevus cells with large amounts of melanin granules showed moderate fluorescence. The tumor cells of melanoma in situ and nevus cells with few melanin granules emitted little fluorescence. Not only malignant melanoma cells but also nevus cells in the formalin fixed specimens had various degrees of fluorescence. Many cases of malignant melanoma emitted intense fluorescence, but this was rarely found in nevocellular nevus. This method is also useful in differentiating melanoma from nevocellular nevus.     

Lymphatic invasion of nevus cells observed in intradermal nevus

A pigmented nevus was observed on the medial aspect of the left scapula of a 30-year-old woman. Histologically, the lesion showed the pattern of a typical intradermal nevus, consisting of type A, B and C cells. However, the most characteristic feature of this intradermal nevus was the projection of polypoid masses of nevus cells containing melanin into the lumen of a lymphatic vessel in the upper dermis. To our knowledge, lymphatic invasion in pigmented nevi is rare; this finding is interesting, if we consider the relationship between nevus cells and lymph nodes.     

Immunohistochemical study of nevocellular nevi

Immunohistochemical analyses were performed on 64 nevocellular nevi (12 compound nevi and 52 intradermal nevi). S-100 protein and its alpha- and beta-subunits were almost always demonstrated in type A, B and C cells, and the staining intensity tended to increase in the type C cells. Neuron-specific enolase was detected in each type of cell; however, the population of positive cells was smaller among type C cells. Beta 2-microglobulin was occasionally demonstrated, but only in type A cells. Vimentin was frequently revealed in every type of cell. Neither myelin basic protein nor glial fibrillary acidic protein was observed in any type of cell. In contrast, normal epidermal melanocytes were positive for vimentin, but negative for S-100 protein and its subunits and neuron-specific enolase. Schwann cells were positive for S-100 protein and its beta-subunit, but negative for the alpha-subunit. Thus, the nevus cells shared a common nature with epidermal melanocytes and Schwann cells which originate from the neural crest; however, the former cells were somewhat different from the latter two kinds and from benign and malignant tumors derived from these cells in the expression of these antigenic substances. Such differences in the expression of antigenic substances may be due to dysontogenic manifestations in nevus cells.     

Transepidermal elimination of nevus cells. A possible mechanism of nevus involution

Nevus cell nests were seen histologically within the upper levels of the epidermis in biopsy specimens obtained from three patients with clinically banal-appearing nevi. Although the presence of melanocytes arranged as solitary units or grouped in nests in the upper layers of the epidermis is one histopathologic feature of malignant melanoma, we believe this finding represents transepidermal elimination of nevus cells and may be one mechanism of nevus involution.     

Expression of c-fos in cultured human nevus cells: an increase over melanocytes and melanoma cells

Abstract Nevus cells exhibit growth characteristics in culture which differentiate them from melanocytes and melanoma cells. We examined the expression of c-jun, c-fos and jun-B mRNA levels in cultures of different melanocytic cell types to determine if biologic differences among these cells was due to their level of proto-oncogene expression. Because cell growth and differentiation are also known to be affected by serum conditions, the expression of c-jun, c-fos and jun-B was examined under normal serum conditions and serum starved and repleted conditions which stimulates proto-oncogene expression. Expression of c-jun and jun-B was not significantly different among the cell types studied under normal serum conditions, or serum starved and refed conditions and c-fos was not detectable in any of the unstimulated cell types. In contrast, when the cells were serum starved and refed, the level of c-fos expression was uniformly increased (2-10 fold) in 3 different nevus ceil lines. This increase was not seen in normal melanocyte cultures or 2 melanoma cell lines. With serum deprivation and repletion, c-fos was also elevated in 1 melanoma cell line. We conclude that the regulation of the proto-oncogene c-fos is different in nevus cells than in normal melanocytes, which may contribute to the different growth characteristics seen with nevus cells.     

Cellular blue nevus with nevus cells in a sentinel lymph node

Regional lymph node involvement by a cellular blue nevus has been reported. However, it has recently been suggested that specific cases with "benign metastasizing" cellular blue nevi are actually rare. This study describes a typical case of a cellular blue nevus with nevus cells in a sentinel lymph node. We demonstrated that a cellular blue nevus clearly involved the regional lymph node and investigated the immunohistochemical profiles of such nodal cellular blue nevus cells. The location of the nevus cells fundamentally indicated a benign type, with limitation to the capsule and the fibrous trabeculae. However, only a few, isolated nevus cells were also seen in the parenchyma of the lymph node. The nevus cells in the capsule and the fibrous trabeculae were positive for c-kit, like the migrating melanocytes from the neural crest. In cellular blue nevi or lesions with similar histopathological features, it may be appropriate to consider the predominant involvement of the capsule as well as the benign cytological features and the immunohistochemical profiles (Ki-67-, PCNA-, and c-kit+) of the nodal cells to be a benign sign.     

Histologic characteristics of vulvar nevocellular nevi

Reports in the literature stress the premalignant potential of vulvar melanocytic lesions and the unusual histologic features associated with some vulvar nevi in premenopausal women. We examined biopsies of 85 pigmented vulvar lesions taken from women 13 to 73 years of age. There were 59 nevocellular nevi, 16 lentigines, 4 melanomas, and 6 miscellaneous lesions. The nevocellular nevi were compared to a control series of 200 nevi from the torsos of women 20 to 60 years old. Three vulvar nevi were considered to be unusual, but not dysplastic. These histologically unusual nevi occurred in women 20 to 30 years old. The lesions exhibited notable enlargement of junctional melanocytic nests with variability in the size, shape and position of the nests. Similar changes were not observed in the control group. There was a significant association (p less than 0.05) between the occurrence of these unusual lesions and their presentation on the vulva; however, these lesions showed no predilection for any particular site on the vulva. There was no evidence of an increased incidence of vulvar dysplastic nevi when compared with the control series.