Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027960 (mole)
 21,279 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The hereditary dysplastic nevus syndrome (DNS) is a well-characterized disorder in which affected individuals have increased numbers of premalignant (dysplastic) nevi and a markedly increased risk of developing cutaneous melanoma. Seeking evidence of a systemic disorder in DNS, we examined the effect of ultraviolet radiation on cultured lymphoid cells. Epstein-Barr virus-transformed lymphoblastoid cell lines from patients with hereditary DNS had similar survival values following treatment with 2.3 to 9.0 J of 254-nm ultraviolet radiation per m2 as did lines from control individuals. Mutagenesis at the hypoxanthineguanine phosphoribosyltransferase locus was assessed by measuring the induction of resistance to thioguanine using a microtiter well assay. Three lymphoblastoid cell lines from patients with hereditary DNS and melanoma had a 2- to 3-fold greater frequency of induced mutants per clonable cell than three normal lines following exposure to 4.5 to 9.0 J of ultraviolet radiation per m2. Expanded clones of mutated DNS lymphoblastoid cell lines had less than 6% of normal hypoxanthine-guanine phosphoribosyltransferase activity. Inhibition and recovery of DNA synthesis following ultraviolet exposure were similar in 2 DNS and 2 normal lines. Repair by DNS lines of ultraviolet-induced DNA damage was in the normal range as measured by alkaline elution. Thus, hereditary DNS exhibits in vitro hypermutability which may reflect increased susceptibility to ultraviolet-induced somatic mutations in vivo. This abnormality may be related to the increased melanoma susceptibility of patients with hereditary DNS.
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PMID:Hereditary dysplastic nevus syndrome: lymphoid cell ultraviolet hypermutability in association with increased melanoma susceptibility. 394 Jun 25

A reliable microscopic differentiation of nevomelanocytic nevi (NMNs) as congenital or acquired would be useful in defining a histogenic relationship between cutaneous melanoma and congenital NMN. In order to delineate histologic differences between congenital NMN and acquired NMN, a standardized assessment was conducted blindly, using a sample of consecutive surgical specimens of NMN submitted to a children's hospital pathology file. Despite significant histologic differences between congenital NMN and acquired NMN, the lack of a reliable prevalence rate for the proportion of congenital NMNs among all NMN specimens submitted for pathologic examination precludes a precise estimate of predictive value for diagnosing a given NMN as congenital or acquired based on histologic features alone. The results of this study can be used neither to support nor to refute a histologic association between cutaneous melanoma and congenital NMN.
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PMID:A histologic comparison of congenital and acquired nevomelanocytic nevi. 403 19

Dysplastic nevi are distinctive cutaneous nevomelanocytic lesions that can be recognized clinically and histologically. They were first described as markers of risk for melanoma in members of hereditary melanoma-prone kindreds. Subsequently, they have been discovered in a significant fraction of patients with sporadic melanoma, and in apparently normal members of the community. It is likely that they constitute markers of risk for melanoma in these populations as well, but that the risk is much less than in members of melanoma-prone kindreds. Beyond their role as risk markers, there is evidence that dysplastic nevi may act as precursors of some melanomas. Thus, their recognition offers an opportunity for analysis of pathogenetic mechanisms in cutaneous melanoma. Most dysplastic nevi, however, are completely stable over long periods of observation. Since up to 5% or even more of the population may bear one or more of these common lesions on their skin, it is important that the profession does not create an epidemic of cancer-phobia by over-emphasizing the significance of a dysplastic nevus. Patients with dysplastic nevi should adopt sensible patterns of skin care.
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PMID:The dysplastic nevus. 404 34

Using an indirect immunoperoxidase technique, 20 nevocellular nevi, 5 dysplastic nevi, 14 primary cutaneous melanomas, and 24 metastatic melanomas were tested with a panel of monoclonal antibodies to monomorphic determinants of Class I (HLA-A,B,C) and Class II (la-like) major histocompatibility complex antigens. Class I HLA and beta 2-microglobulins were not detected on the majority of nevus cells but were expressed by 3 of 5 dysplastic nevi, by the majority of tumor cells in 12 of 14 primary cutaneous melanomas, and in 13 of 24 metastases. The different expression of Class I HLA and beta 2-microglobulins in primary and metastatic lesions suggests that loss of these antigens may be associated with progression of malignancy. Class II HLA were not detected in common nevi but were locally present in 1 of 5 dysplastic nevi, 7 of 14 cases of primary cutaneous melanoma, and all 24 cases of metastatic lesions tested. These findings suggest that increase in Class II HLA expression may be associated with progression of malignancy. The staining patterns obtained with monoclonal antibodies to distinct determinants of Class I HLA and Class II HLA were superimposable within each type of antigen. Therefore, the discrepancies in the literature about the expression of histocompatibility antigens by lesions of melanocytic origin are not likely to reflect the different specificity of the antibodies used by the various investigators.
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PMID:Immunohistochemical analysis of malignant melanomas and nevocellular nevi with monoclonal antibodies to distinct monomorphic determinants of HLA antigens. 620 49

Dysplastic melanocytic nevi (DMN) are distinguished histologically by a hyperplasia of variably atypical intraepidermal melanocytes in a lentiginous epidermal pattern. In order to further characterize the intraepidermal melanocytes of DMN, 4 representative specimens each of DMN, acquired nevocellular nevi (NCN), solar lentigines (SL), and superficial spreading melanoma (SSM) were selected on the basis of predetermined criteria, confirmed in a blind histologic assessment, and compared in a quantitative morphologic study using 6 micron-thick hematoxylin and eosin stained sections of L-dihydroxyphenylalanine (dopa) preincubated vertical tissue slices of lesion and adjacent normal skin. The average melanocyte frequency, expressed as the percent of dopa-reactive perikarya among 600 consecutive basal unit cells, was significantly greater in DMN (60 +/- 23%) than in NCN (18 +/- 3%), SL (25 +/- 7%), and adjacent skin (14 +/- 3%), but similar to that in SSM (71 +/- 11%). The average mean diameter of 200 consecutive epidermal basal unit melanocytes was significantly larger in DMN (11 +/- 2 microns) than in NCN (7 +/- 0.4 microns), SL (6 +/- 0.1 microns), and adjacent skin (6 +/- 0.4 microns), but significantly smaller than in SSM (16 +/- 3 microns). The observed similarities of intraepidermal melanocytes in selected DMN and SSM, as well as distinct differences from melanocytes in selected NCN and SL, support the hypothesis that some varieties of DMN may represent potential precursors of cutaneous melanoma.
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PMID:Increased intraepidermal melanocyte frequency and size in dysplastic melanocytic nevi and cutaneous melanoma. A comparative quantitative study of dysplastic melanocytic nevi, superficial spreading melanoma, nevocellular nevi, and solar lentigines. 634 76

In 1916 patients with primary malignant melanoma of the skin (excluding palms, soles, and nailbeds) the primary lesions were reviewed microscopically and classified according to Clark's system into lentigo maligna melanoma (85), superficial spreading melanoma (1234), and nodular melanoma (513). Differentiation between the types was not possible in 84 melanomas (4%). By correlating type of melanoma with various clinical and histological features, it was found that the 3 types differed significantly from one another with regard to growth rate of tumor, antecedent nevus, dominant type of invasive tumor cell, and prognosis. The study thus supported the basic principle of the classification employed, that the 3 histological types represent distinct entities of cutaneous melanoma with different clinical, cellular, and behavioral characteristics. As originally described by Clark, the growth rate was greatest for nodular melanoma, followed by superficial spreading melanoma, and least for lentigo maligna melanoma. It is recommended that this classification be employed in the histological typing of cutaneous melanoma as 1) it is readily applied to the vast majority of melanomas, and 2) it seems to delineate separate clinico-pathologic entities of cutaneous melanoma, which might be correlated with aetiological differences.
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PMID:Histological type and biological behavior of primary cutaneous malignant melanoma. 1. An analysis of 1916 cases. 641 9

Dysplastic melanocytic nevi (DMN) are irregularly pigmented lesions characterized by (1) atypical melanocytic hyperplasia in a lentiginous epidermal pattern (AMHL), (2) one or more dermal mesenchymal changes, and (3) frequently a dermal nevocellular nevus. In order to determine an association between DMN and cutaneous melanoma, the dominant histologic feature of DMN (namely, AMHL) was sought in histologic contiguity with 234 primary melanomas. Of these 234 cases, 9 were lentigo maligna melanomas. Of the remaining 225 cases, 49 (21.8%) were associated with AMHL in the same histologic section as (but beyond the most lateral margin of) intraepidermal and invasive melanoma. AMHL was directly associated with the presence of dermal nevocellular nevi in histologic contiguity with melanoma, and a greater number of histologic slides with melanoma available for review. AMHL was inversely associated with nodular melanoma. Most of the AMHL cases were not associated with familial melanoma, but the total number of familial cases was low. The histologic association between AMHL and melanoma in one fifth of cases in this series supports the hypothesis that at least some cutaneous melanomas may have an origin in DMN.
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PMID:Dysplastic melanocytic nevi in histologic association with 234 primary cutaneous melanomas. 663 Jun 18

A study Of the uveas of white patients with known cutaneous melanoma and white control subjects showed that patients with cutaneous melanoma had a significantly higher frequency of iris nevi (101 of 197 patients, 51%) than control subjects (58 of 147 subjects, 39%). The frequency of choroidal nevi was also higher in the group with cutaneous melanoma but the number (eight of 197 patients compared with two of 147 control subjects) involved was too small for statistical significance to be assessed. Patients with cutaneous melanoma, particularly women, had more skin nevi than did control subjects.
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PMID:Uveal findings in patients with cutaneous melanoma. 683 89

The occurrence of cutaneous melanoma and intraocular melanoma as double primary cancers in the same patient and in different members of the same family has suggested that these two forms of melanoma are etiologically related. It is theoretically possible that the link between these two pigment cell malignancies may be the dysplastic nevus syndrome, and patients with the dysplastic nevus syndrome may have an increased risk of intraocular melanoma and cutaneous melanoma. We studied two new kindreds in which cutaneous melanoma, intraocular melanoma, and the dysplastic nevus syndrome occurred and conducted neuro-ophthalmologic examinations of 26 patients with hereditary cutaneous melanoma or the dysplastic nevus syndrome, or both. In the one family studied in detail, the cutaneous melanoma predisposition came from the paternal bloodline, whereas the intraocular melanoma occurred in the maternal bloodline. The ophthalmologic examinations disclosed neither intraocular melanoma nor suspicious or atypical choroidal nevi. Our limited data suggested that the association of intraocular melanoma with cutaneous melanoma and dysplastic nevus syndrome may be coincidental.
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PMID:The familial occurrence of cutaneous melanoma, intraocular melanoma, and the dysplastic nevus syndrome. 688 Dec 47

The relative risk of melanoma associated with small congenital nevi was estimated by comparing the published frequency of histologically documented nevocellular nevi in newborn infants with the frequency of: (1) congenital nevi at the tumor site, ascertained by history in 134 patients with melanoma; and (2) tumor-associated nevi with congenital features in 234 melanoma specimens. A 21-fold increase in melanoma risk was estimated for persons with small congenital nevi when nevi were ascertained by history, and a three- to tenfold increase in risk when nevi were ascertained by histology. Based on these approximations of relative risk from historic and histologic methods of detection, persons with small congenital nevi who live to age 60 are estimated to have cumulative risks for melanoma of 4.9/100 and 0.8 to 2.6/100, respectively. The increased risk is related presumably to the markedly increased probability of melanoma arising in association with small congenital nevi. In other words, small congenital nevi may represent precursors for at least some cases of cutaneous melanoma. The estimated risk are highly dependent on the specificity of methods used for ascertainment of congenital nevi.
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PMID:Small congenital nevocellular nevi and the risk of cutaneous melanoma. 705 29


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