摘要:

Examination of 38 human melanoma samples by Western blotting analysis with anti-gelsolin antibodies showed that a new 85 kDa truncated gelsolin (GSNp85), co-expressed with wild-type gelsolin, was frequently expressed in vertical growth phase melanomas (Clark level II–IV) and metastatic growth phase melanomas. The GSNp85 truncate was not expressed in radial growth phase melanomas (Clark level I), acquired naevi, other skin cancers or normal skin tissues. Peptide-sequencing analysis revealed that GSNp85 lacks the C-terminal domain of wild-type gelsolin at the region containing the caspase-8 recognition site IETD. Caspase-8 processing was detected in GSNp85-positive but not GSNp85-negative melanomas. These data suggest that GSNp85 is a cleavage product of caspase-8 and may be useful as a new marker for the vertical or metastatic growth phase of malignant melanoma.

ISSN:0960-8931    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

The presence and characteristics of androgen receptors (ARs) have been described by our group in one human melanoma cell line. We have now investigated their presence in two other human melanoma cell lines, IIB-MEL-LES and IIB-MEL-IAN, as well as in biopsies from human metastatic melanoma. Scatchard analysis revealed a single binding component for both cell lines, the apparent dissociation constant obtained being 15 nM, with a binding capacity of 280 fmol/mg total cell protein, for IIB-MEL-LES cells and 14 nM, with a binding capacity of 206 fmol/mg total cell protein for IIB-MEL-IAN cells. When specificity was assessed, not only androgen and anti-androgen but also non-androgenic compounds were able to compete for [3H]R1881 binding, as seen before. When immunocytochemistry of IIB-MEL-LES and IIB-MEL-IAN cells was performed for ARs, both cell lines were deeply stained in the nucleus, whereas no staining was found for oestrogen or progesterone receptors. Every specimen of melanoma metastases tested for the presence of ARs was deeply stained, and in the majority the intensity of the staining was high. Several hormones and anti-hormones were tested for their ability to affect cell proliferation. In both cell lines, testosterone, dihydrotesterone, oestradiol and progesterone significantly stimulated cell proliferation, and this was reversed by hydroxyflutamide, bicalutamide or tamoxifen.

ISSN:0960-8931    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

While mutations ofCDKN2Aare associated with melanoma predisposition, the precise role of its gene product p16 in the development of sporadic melanoma is less clearly understood. We sought to determine the prevalence of p16 expression using immunohistochemical analysis in a population-based sample of melanoma tumours, and also to identify histological, phenotypic and environmental factors associated with the presence or absence of p16 expression. We conducted face-to-face interviews with 108 patients newly diagnosed with melanoma to ascertain their history of sun exposure, and recorded various phenotypic parameters. Paraffin sections of tumours from these patients were stained with an anti-p16 monoclonal antibody following antigen retrieval. Overall, 52 (48%) tumours expressed p16; nodular melanomas had significantly lower levels of p16 immunoreactivity than superficial spreading melanomas (P= 0.015). While no association was found between p16 expression and host phenotype, loss of p16 staining was associated with thicker lesions (p= 0.084) and a high mitotic index (P= 0.013). Taken together, these findings are consistent with loss of p16 being a late event in the progression of sporadic primary melanomas, being associated with tumours of a more aggressive nature.

ISSN:0960-8931    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

Primary cutaneous malignant melanomas (CMMs) from 26 individuals belonging to nine families with an identifiedCDKN2Amutation were clinically and histopathologically compared with 78 matched CMM controls and with a population-based series of CMMs (n= 667). All tumours were histopathologically re-examined.CDKN2A-associated cases were significantly less invasive compared with the matched controls, with an adjusted odds ratio (adjOR) of 2.9 and a 95% confidence interval (CI) of 1.0–8.1 (P= 0.04). According to the odds ratio (OR) values,CDKN2A-associated cases seemed to have tumours more often located on the head and neck (adjOR 2.9, 95% CI 0.6–13.7), with less inflammation (adjOR 0.7, 95% CI 0.3–1.8) and regression (adjOR 0.6, 95% CI 0.2–1.8) but more frequent histological ulceration (adjOR 1.9, 95% CI 0.6–5.8). In comparison with the population-based material,CDKN2A-associated cases were significantly younger at diagnosis (crude OR 3.5, 95% CI 1.6–7.5, divided at 50 years) and had less regressive reaction in their tumours (crude OR 0.35, 95% CI 0.2–0.8). No significant differences were seen for tumour thickness between the different groups. On multivariate analysis, the overall survival was significantly worse for thicker tumours and older age (P= 0.04 for both). To our knowledge this is the first description of the histopathological features of CMMs from families with mutations in theCDKN2Agene.

ISSN:0960-8931    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

Germ-line mutations of theCDKN2Atumour suppressor gene have been reported in association with familial melanoma, sporadic melanoma with multiple primary lesions and also pancreatic cancer. We studied the hypothesis that patients with melanoma and additional unrelated cancers may harbour mutations in theCDKN2Agene. Twenty seven patients with histologically confirmed melanoma who also had additional cancers such as breast, colorectal, lymphoma and other neoplasms were studied. We also examined 17 additional patients, 13 of whom had a first-degree relative with melanoma and four who had two or more primary melanomas. Some patients belonged to more than one of these categories. No mutations of theCDKN2Atumour suppressor gene were detected among patients with melanoma and additional cancers. The previously described Met53IleCDKN2Amutation located in exon 2 was detected in a female patient with melanoma metastatic to the regional lymph nodes, multiple primary cutaneous lesions, atypical naevi and a first-degree relative with melanoma. The studied cohort is too small for firm conclusions. However, it would appear that melanoma and additional, apparently unrelated, cancers developing in the same individual are likely to be related to a combination of low-risk susceptibility genes and environmental factors.

ISSN:0960-8931    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

Deletions detected in cytogenetic and loss of heterozygosity (LOH) studies indicate that at least one tumour suppressor gene maps to the long arm of chromosome 10. Previous deletion mapping studies have observed LOH on 10q in about 30% of melanomas analysed. ThePTENgene, mapping to chromosome band 10q23.3, encodes a protein with both lipid and protein phosphatase activity. Somatic mutations and deletions inPTENhave been detected in a variety of cell lines and tumours, including melanoma samples. We performed mutation analyses and extensive allelic loss studies to investigate the role this gene plays in melanoma pathogenesis. We found that a total of 34 out of 57 (60%) melanoma cell lines carried hemizygous deletions of chromosome 10q encompassing thePTENlocus. A further three cell lines carried smaller deletions excludingPTEN. Inactivation of bothPTENalleles by exon-specific homozygous deletion or mutation was observed in 13 out of 57 (23%) melanoma cell lines. The mutation spectrum observed does not indicate an important role for ultraviolet radiation in the genesis of these mutations, and evidence from three cell lines supports the acquisition ofPTENaberrations in culture. Ten out of 49 (20%) matched melanoma tumour/normal samples harboured hemizygous deletions of either the whole chromosome or most of the long arm. Mutations withinPTENwere detected in only one of the 10 tumours demonstrating LOH at 10q23 that were analysed. These results suggest thatPTENinactivation may be important for the propagation of melanoma cells in culture, and that another chromosome 10 tumour suppressor gene may be important for melanoma pathogenesisin vivo.

ISSN:0960-8931    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

The status and relevance of repetitive nucleotide sequences or microsatellite alterations in sporadic cutaneous melanoma has not been fully clarified. In this study we evaluated the presence of microsatellite alterations in a series of sporadic primary and metastatic melanomas in order to discover which genetic events may have a pathogenetic role in the development of this disease. Tumour samples were obtained from 21 patients with sporadic cutaneous melanoma, and from eight corresponding positive sentinel lymph nodes and one corresponding in-transit metastasis. In each specimen, selected neoplastic cells were procured by laser-assisted microdissection. Polymerase chain reaction-based microsatellite analysis was performed using a panel of 11 microsatellite markers, located at chromosome 2p, 4q, 9p, 16q, 17p and 21q. Overall, we found microsatellite alterations in five (23.8%) melanomas. Of these, one case showed alteration at marker D2S2182 and one at marker D17S261, whereas in another case alterations at three loci, D2S2182, D2S2291 and D9S171, were found. The fourth patient demonstrated an alteration at locus D9S171 both in the primary tumour and in the histologically positive sentinel lymph node. The fifth case was characterized by alterations at D2S2182 and at D17S250, whereas the corresponding in-transit metastasis showed the same alterations as the primary tumour and an additional alteration at IFNα. In conclusion, our study confirms previous observations that cutaneous melanomas demonstrate microsatellite alterations, although such instability occurs at a lower frequency than specific mismatch repair defects. Genetic analysis of metastatic lesions revealed that the same microsatellite alterations as in the primary tumour are seen, but additional genetic changes may develop during disease progression.

ISSN:0960-8931    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

Circulating malignant cells in peripheral blood are thought to be precursors and surrogate markers of distant metastases and hence markers of a poor clinical outcome. In this study, we used the detection of MART-1 and tyrosinase (TYR) mRNA with a quantitative reverse transcription-polymerase chain reaction (RT-PCR) assay to identify circulating melanoma cells. Blood samples were obtained from 35 patients with metastatic melanoma before, during and after treatment with interleukin-2, interferon-α and cisplatin. In addition, MART-1 and TYR protein was identified by immunohistochemistry in consecutive biopsies from 15 of the patients. Analysis of three daily blood samples for 3 days demonstrated that four out of 11 patients examined were negative for both markers on all occasions, and two patients were positive for both markers on all occasions but one. The remaining five patients showed sporadic low positive results for one or the other of the two markers. By comparing the immunohistochemistry results from consecutive biopsies with the RT-PCR results, we demonstrated that patients with MART-1 and TYR protein in their tumour cells had circulating MART-1 and TYR mRNA in 77% and 54% of the cases, respectively. During treatment, the majority of patients who were positive for MART-1 and TYR mRNA converted to being negative. However, these conversions did not significantly correlate with objective response. The presence of TYR mRNA in one of the first two samples showed a trend towards being an independent prognostic factor for poor survival.

ISSN:0960-8931    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

The aim of this study was to evaluate the tumour-associated antigen melanoma inhibitory activity (MIA) as a potential novel serological tumour marker in primary and metastatic uveal melanoma in both the laboratory and the clinical setting. In the laboratory setting, immunohistochemical staining with MIA antibody was performed in paraffin-embedded tissues from six amelanotic uveal melanomas and eight metastatic lesions of uveal melanomas. In the clinical setting, serum samples of 139 patients with uveal melanoma were examined; eight of these patients had overt metastatic disease. Sixty-one initially metastatic disease-free patients were followed over time (median follow-up 240 days, 95% confidence interval 60–883 days) and MIA levels were assessed repeatedly. A one-step enzyme-linked immunosorbent assay was used to quantify the MIA serum levels. In the laboratory setting, five of the six primary uveal melanomas and seven of the eight metastatic lesions stained immunohistologically positive for MIA. In the clinical setting, the 131 patients without overt metastatic disease demonstrated a median serum concentration of MIA of 6.6 ng/ml. In the eight patients with overt metastatic disease, the median serum concentration of MIA was 26.28 ng/ml. This difference was highly statistically significant (P< 0.001, analysis of variance). During follow-up, three initially metastatic disease-free patients developed overt metastatic disease, and the MIA level increased from a median of 6.6 ng/ml before to 29.2 ng/ml after clinical detection of metastatic disease. In the 58 other patients, the serum level remained stable during the entire follow-up period. In conclusion, MIA is expressed in primary and metastatic lesions of uveal melanomas, and a statistically significant elevation in MIA serum levels in patients who develop metastatic disease due to uveal melanoma indicates its promising role as a serum marker for monitoring uveal melanoma patients for metastasis.

ISSN:0960-8931    

出版商:OVID    

年代:2002

数据来源: OVID

摘要:

Dermoscopy is a non-invasivein vivotechnique that can be utilized for the clinical diagnosis of pigmented lesions. The aim of this study was to assess the utilization and beliefs about the usefulness of dermoscopy in the evaluation of pigmented lesions by physicians in dermatology residency programmes, and to determine the extent of dermoscopy training received by residents in these programmes. Questionnaires were sent to the directors of all the accredited dermatology residency programmes in the United States (n= 105). A follow-up postcard questionnaire was sent to the chief resident of all the responding programmes. Eighty-three physicians responded to the questionnaire (79%). Fifty-one per cent of the respondents (n= 42) reported utilizing dermoscopy. Reported reasons for using dermoscopy by respondents included the fact that it helps detect melanoma early (74%), leads to fewer biopsies (74%) and reduces patient anxiety (64%). Lack of training (51%) and lack of usefulness (42%) were amongst the reported reasons for not utilizing dermoscopy. Sixty-seven per cent of respondents reported an increase of approximately 50% in the use of dermoscopy over the past 5 years, and 45% anticipated an increase in use over the next 5 years. Thirty-eight per cent of chief residents from the responding programmes reported receiving training in dermoscopy during residency. In conclusion, half of the dermatology residency programmes currently use dermoscopy in the evaluation of pigmented lesions. The main reason for not using dermoscopy was a lack of training. Respondents anticipated a future increase in the use of dermoscopy.

ISSN:0960-8931    

出版商:OVID    

年代:2002

数据来源: OVID