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Query: UMLS:C0025202 (melanoma)
 69,561 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Topical application of 4-tertiary butyl catechol (TBC) causes vitiligo in the skin of man and animals, and previous electron microscopic studies showed pheomelanin formation in the affected areas. In the present study, we investigated changes of enzyme activities, eumelanin content and amount of sulfur in tissue cultured human melanoma cells exposed to the depigmenting chemical. TBC enhanced glutathione reductase activity without changing the eumelanin content by 24 hr after exposure and subsequently (by 42 hr) increased gamma-glutamyl transpeptidase activity and sulfur content in the cells with a decrease in eumelanin content. It is suggested that this chemical alters the types of melanin formed by modulation of these enzyme activities.
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PMID:Reduction in eumelanin by the activation of glutathione reductase and gamma-glutamyl transpeptidase after exposure to a depigmenting chemical. 613 32

Immunoprecipitation was used to assay for antibodies to normal human melanocytes in the sera of 12 patients with common vitiligo and 12 normal individuals. The procedure is based on the specific immunoprecipitation using protein A-sepharose of antibodies binding to detergent-soluble, radioiodinated macromolecules of normal human melanocytes grown in culture. Antibodies to melanocytes were found in all 12 patients with vitiligo but in none of the normal sera. None of the sera reacted specifically to normal human fibroblasts or to human melanoma cells radioiodinated in a similar manner. These observations suggest that antibodies to melanocyte-associated antigens are present in common vitiligo.
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PMID:Detection of antibodies to melanocytes in vitiligo by specific immunoprecipitation. 619 21

Most patients with active vitiligo (82% of 61) have antibodies to antigens of normal human melanocytes that can be detected by specific immunoprecipitation of radioiodinated, detergent-soluble, melanocyte macromolecules. Such antibodies were present in only 12% of patients with melanoma and in none of 35 patients with nonpigmentary skin diseases. The antibodies were directed to a common antigen(s) on melanocytes that was not present on normal fibroblasts or keratinocytes. These observations suggest that vitiligo is an autoimmune disease mediated by antibodies to melanocyte-associated antigen(s).
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PMID:Antibodies to normal human melanocytes in vitiligo. 634 14

Sera of patients with various types of vitiligo have been found to contain circulating antibodies for the cytoplasmic components of human melanoma cell lines. This incidence is high, especially in generalized vitiligo vulgaris with or without Sutton's phenomenon. There is good correlation between the antibodies and positive microsome test, thyroid test, DNA test, as well as the effect of steroid ointment.
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PMID:Immunopathology of vitiligo vulgaris, Sutton's leukoderma and melanoma-associated vitiligo in relation to steroid effects. I. Circulating antibodies for cultured melanoma cells. 637 58

Our laboratory has recently reported that over 80% of patients with common vitiligo have circulating antibodies to cell-surface antigens on normal human melanocytes. The slow growth rate of these cells limits the assays that can be performed for antibody detection. We now have found that the antigens defined by vitiligo sera on melanocytes are also expressed on FF cells, a revertant line of hamster melanoma cells. These antigens can be detected both by indirect immunofluorescence and specific immunoprecipitation assays. The presence of "vitiligo" antigens on hamster FF cells will aid further study of the abnormal immune response in vitiligo.
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PMID:Expression of vitiligo antigen on a revertant line of hamster melanoma cells. 638 93

We found twelve families with melanoma who had close family members with halo nevi, early graying of hair, a halo primary melanoma, or ordinary vitiligo. On the basis of these findings and the observation of others in fish, horses, and pigs with melanomas, we suggest that the melanocytes of people with vitiligo or with a genetic background for vitiligo are predisposed to undergo a malignant transformation. The presence of vitiligo appears as a manifestation of host suppression of malignant melanocytes.
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PMID:Vitiligo and melanoma: can genetically abnormal melanocytes result in both vitiligo and melanoma within a single family? 649 Sep 94

A cutaneous depigmentation occurring either far, or the primary tumour, or about the excision scar, or appearing in different other conditions was noted 29 times among 500 cases of malignant melanoma. Before excision, a vitiliginous depigmentation was present only in two patients. Nevertheless 9 patients observed a vitiligo after surgical excision of the tumour (2.5 years after, as an average) this proportion must conjecturally increase thereafter and so represent a minimal score. Twice, an achromic halo was obvious around the primary melanoma. In seven patients there was evidence of secondary depigmentation around the excision. Seven times a localized achromia was observed on the site of BCG-application or DNCB-test. Two patients had a halo-naevus (Sutton naevus). These varying achromias accompanying malignant melanoma were largely studied in animal pathology (horse and chimpanzee). They are usually in animals a factor of good prognosis. This good prognosis was likewise related in human malignant melanoma, but our series is against the assertion of any prognosis significance.
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PMID:[Cutaneous achromia and malignant melanoma]. 652 18

We have identified and studied twenty-seven patients with melanoma who also had vitiligo. Four patients had vitiligo before the diagnosis of melanoma, and twenty-three developed depigmentation after the diagnosis of malignancy. We also have reviewed published reports about twenty-four other patients with melanoma who developed vitiligo. The clinical course of the melanoma in the fifty-one patients was remarkably similar. Thirty-seven had a melanoma arising at a site which tends to carry a poor prognosis, for example, on the trunk, under the nail, or on the mucous membranes. Forty-nine patients had metastases in regional lymph nodes or at distal sites. Thirty-three patients survived 5 years, and twenty-five survived 10 years. These data suggest that the appearance of vitiligo in patients with metastatic melanoma portends a longer survival than expected. The patients with vitiligo are not necessarily cured and eventually may succumb to metastatic disease. We were unable to determine whether the vitiligo caused retardation of tumor growth or whether the melanoma caused vitiligo.
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PMID:Vitiligo in patients with metastatic melanoma: a good prognostic sign. 664 67

We report clinical and ultrastructural results in eight patients with melanoma and widespread leukoderma. Leukoderma appears to be a good prognostic sign. Although some features of this entity are suggestive of vitiligo, the patients' age, the distribution and appearance of body lesions, and ultrastructural results show a more varied clinical and ultrastructural spectrum. The high frequency of ocular pigmentary disturbances and uveitis in this patient population is noteworthy and deserves further study. We would recommend routine use of Wood's light examination in following patients with thick stage I, stage II, or stage III melanoma to facilitate detection of this phenomenon.
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PMID:Malignant melanoma and vitiligo-like leukoderma: an electron microscopic study. 664 68

Two patients are reported who were treated with 8-methoxypsoralen and ultraviolet A (PUVA) for psoriasis and developed cutaneous lesions of malignant melanoma in situ (atypical melanocytic hyperplasia). One patient received 324.5 joules/cm2 of UVA. Seven months after discontinuing therapy, he developed a superficial spreading melanoma in situ in association with an intradermal nevus on the left posterior thoracic area. The second patient received 2,802 joules/cm of UVA. While on PUVA therapy she developed an in situ lentigo melanoma on her lower lip. To our knowledge only one other psoriatic patient and one patient with vitiligo have developed malignant melanomas after PUVA therapy, so that an increased incidence of malignant melanomas after PUVA therapy, so that an increased incidence of malignant melanoma following PUVA is not documented.
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PMID:Malignant melanoma in situ in two patients treated with psoralens and ultraviolet A. 664 89


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