Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0025202 (melanoma)
 69,561 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We investigated the role of signal transduction systems in the attachment of human uveal melanoma cells to matrix proteins. Ocular melanoma cells established from primary tumours attached rapidly to all substrates examined. Preferred substrates of attachment were collagens type I, III and IV and fibronectin rather than laminin, gelatin, arginine-glycine-aspartine, vitronectin, poly-L-lysine or plastic. All cells showed rapid attachment to the preferred substrates (80% within 10 min). Manipulation of intracellular cyclic AMP or protein kinase C activity had relatively little effect on cell attachment. In contrast, attachment was significantly reduced by manipulating either intracellular calcium or calmodulin. After 15 min at 37 degrees C, the calcium ionophore ionomycin (5 microM) reduced attachment to 25%, and TMB8 (50 microM), which can reduce intracellular calcium, reduced attachment to 60%. The experimental calmodulin antagonist J8 (25 microM), a substituted naphthalene sulphonamide, reduced attachment to 40%. Similarly tamoxifen (25 microM), which has calmodulin antagonist activity in vitro, reduced attachment to 55%. Both J8 and tamoxifen inhibited cell attachment to a wide range of matrix proteins, suggesting that this effect on attachment is not dependent on the presence of specific adhesion receptors. Reduction of ocular melanoma tumour cell/matrix interactions through manipulation of intracellular calcium or calmodulin may therefore merit further investigation as a possible approach to reducing metastatic spread.
 ...
PMID:Investigation of the role of signal transduction in attachment of ocular melanoma cells to matrix proteins: inhibition of attachment by calmodulin antagonists including tamoxifen. 792 90

For several years, immunoscintigraphy (IS) using a 99mTc-labeled monoclonal antibody for tumor localization has been used as an additional tool in the diagnosis of malignant melanoma. The aim of our study was to verify previously published data with respect to our own patients and to correlate immunoscintigraphic results with histological findings. In particular, we wanted to compare the outcome of IS in ocular melanoma with that in cutaneous melanoma. We examined 28 patients (15 females, 13 males, average age 64 years) with clinically suspected ocular melanoma. IS was performed using the monoclonal antibody 225.28S (Tecnemab-K-1, Fa. Sorin/Solco), and images were obtained in a standard fashion (planar) as well as with the SPECT technique. In 16 patients, the tumor was examined afterwards histologically. The control group consisted of 102 patients with histologically proven metastasizing cutaneous melanoma who were investigated by IS in an identical fashion. In contrast to the literature published so far, we demonstrated a positive IS reaction in only 42% (and 56% in histologically proven cases, respectively) in our patients with ocular melanoma, while in patients with cutaneous melanoma, we found a sensitivity of more than 80%. In the 3 patients who turned out not to have ocular melanoma, we found one false-positive reaction (subretinal hemorrhage). No correlation was found between the various histological features of ocular melanoma and the immunoscintigraphic results. We conclude that IS using the antibody 25.28S is of limited value in patients with ocular melanoma and should only be recommended in selected cases.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:[Immunoscintigraphy results in the comparison of ocular with cutaneous melanoma]. 795 Jan 29

Several cell lines have been derived from an ocular melanoma obtained from an enucleated patient. Three cell types are observed during the time in culture of all the cell lines under study. Two of them have epithelial and spindle shape respectively. A third cell type, having a spheroidal shape, is formed from spindle cells and may be transformed into epithelial cells upon re-seeding. Further experiments showed that the same cell may change of shape following the cycle: spheroidal-->epithelial-->fusiform-->spheroidal. Scanning microscopy shows the coexistence of the three cell shapes in the same culture and the presence of several filaments and processes protruding at the surface of the cells. Transmission electron microscopy shows that the cell lines, in general, contain melanosomes empty or fairly pigmented and several filaments and microtubules. The presence of melanin may be stimulated by seeding of melanoma cells over a "feeder layer" of fibroblasts.
 ...
PMID:[Morphological characterization of cell lines of human uveal melanoma]. 798 88

Ocular melanoma, the most common primary adult intraocular neoplasm, has a very high morbidity and mortality despite multiple alternative therapies. Consequently, we decided to study Gamma Knife radiosurgery (GKR) for the treatment of ocular melanoma in a clinical trial format. We describe the modifications of standard GKR to treat intraocular tumors, the objective, inclusion and exclusion criteria, treatment parameters, measurement of effect, and statistical evaluation of the clinical trial. The major adverse effects (i.e., cataract, vitreous hemorrhage, blindness, and loss of the eye) of the study are correctable or infrequent, whereas the benefits (i.e., tumor stasis or regression, preservation of sight, lower metastatic potential, and preservation of the globe) are substantial. This study is designed to evaluate GKR as a treatment option for ocular melanoma, although results are not yet available.
 ...
PMID:Gamma Knife radiosurgery in the treatment of ocular melanoma. 811 54

In the attempt to contribute to a correct and early diagnosis of melanoma, this paper critically evaluates, in 40 patients with cutaneous localization and 20 with ocular localization, the results of immunoscintigraphy with 99mTc-225.28S-F(ab')2 and the clinical, instrumental and biopsy findings. While the cutaneous melanoma group is mainly composed of patients subjected to surgical exeresis of the lesion before radioimmunoscintigraphy (RIS), the ocular melanoma group is composed of patients with the primary lesion in situ or previously treated with contact radiotherapy. In the cutaneous melanoma group 5 cases presented falsely positive immunoscintigraphic findings, and only 2 falsely negative. In the ocular melanomas, the percentage of false negatives was higher (n = 7). This is probably attributable to the antigenic expressivity, higher in the metastases than in the primary melanomas. The cases of particular interest are discussed in relation to the clinical picture, to the instrumental examinations and to the histological findings. The work made it possible to contribute to a more correct interpretation of the RIS findings in the staging and follow-up of cutaneous and ocular melanomas.
 ...
PMID:Radioimmunoscintigraphy with 99mTc-225.28S-F(ab')2 in cutaneous and ocular melanomas: cases of particular clinical interest. 817 59

The American College of Surgeons performed a patient care and evaluation study of malignant melanoma for 1981 and 1987 to determine the presenting symptoms, methods of evaluation, clinical management and resulting outcome. A previous report on malignant melanoma of the skin has been published. This report details the findings of 245 ocular melanomas in 1981 and 275 ocular melanomas in 1987. Most of the ocular melanomas were uveal. The patients with ocular melanoma were older than the patients with skin melanoma. No significant difference was found in the number of ocular instances by gender and by study year. A high percentage of non-Hispanic Caucasians were documented with this disease, and a high percentage of ocular melanomas were not classified by the standard Callender classification. A significant number of melanomas had pigmentation, and a significant number of patients had imaging studies that, in the absence of an elevated alkaline phosphatase, usually yielded negative results. Most patients were treated with enucleation, with an increase in frequency of radiation therapy from 1981 to 1987. Local and regional recurrence was not a problem, but systemic metastases occurred frequently. Type of histologic factors by the Callender classification had an influence on survival.
 ...
PMID:Patient characteristics, methods of evaluation and treatment of ocular melanoma in the United States for the years 1981 and 1987. 821 2

Investigators who conduct clinical trials of treatments for uncommon conditions face special challenges regarding trial design and execution in addition to the challenges faced by all clinical trial investigators. The Collaborative Ocular Melanoma Study (COMS) currently consists of two multicenter, randomized controlled clinical trials designed to investigate the efficacy of radiotherapy compared to surgery in prolonging the survival of patients with choroidal melanoma, a rare intraocular cancer. Patients with unilateral choroidal melanoma classified as "medium" in size are randomized with equal probability to either enucleation (removal of the eye) or radiation delivered to the tumor by means of a radioactive "plaque" attached by sutures to the scleral surface of the eye over the base of the tumor. Patients with large tumors are randomized with equal probability to either enucleation or a 5 day course of external beam radiation therapy followed by enucleation. Time to death is the primary outcome; patients will be followed for at least 10 years or until death. Quality assurance mechanisms for evaluation, treatment, and follow-up have been implemented. This paper describes the design and methods of the trials, highlights the challenges associated with implementing and conducting the study, and summarizes the current status of the study.
 ...
PMID:Design and methods of a clinical trial for a rare condition: the Collaborative Ocular Melanoma Study. COMS Report No. 3. 822 68

Indocyanine green (ICG)-enhanced laser therapy was evaluated for the treatment of experimental intraocular melanoma. Immediately after an intravenous injection of ICG, a 790-nm chromophore, 810-nm semiconductor diode laser was used to irradiate Greene hamster melanomas that had been implanted in the iris of rabbits. ICG-enhanced laser treatment of melanoma (14 eyes) was compared with treatment by laser alone (4 eyes), ICG alone (1 eye), and no treatment (2 eyes). Tumors treated with ICG-enhanced laser showed no growth after treatment, as judged by clinical examination and photography. Histologically, 4 of the 14 tumors treated with ICG-enhanced laser showed total necrosis, whereas the remaining 10 tumors treated similarly demonstrated only rare viable cells around blood vessels or at the tumor periphery. Laser treatment without ICG enhancement resulted in only superficial tumor necrosis, and all four of these tumors continued to grow after treatment. With further evaluation, indocyanine green in combination with a commercially available diode laser may be useful in the treatment of ocular melanoma.
 ...
PMID:Indocyanine green-enhanced diode laser treatment of melanoma in a rabbit model. 823 10

The management of malignant melanoma of the ciliary body and choroid (posterior uvea) is controversial. Authorities have disagreed about whether enucleation or conservative treatment offers the best prognosis. Although retrospective studies have suggested that the method of treatment makes no difference in the systemic prognosis, new studies in which the various therapeutic modalities are being compared are currently under way. The Collaborative Ocular Melanoma Study is attempting to address some of these issues in a randomized clinical trial. In this report, the currently available methods for managing posterior uveal melanoma are reviewed. Small asymptomatic choroidal melanomas can probably be observed periodically until evidence of growth is documented. Some small choroidal melanomas can be treated with laser photocoagulation. Alternatively, radiotherapy (either episcleral application of a radioactive plaque or charged particle irradiation) can be used. Although the two methods of radiotherapy seem equal relative to the development of systemic metastatic lesions, plaque radiotherapy is associated with fewer and less severe local complications. Selected melanomas of the ciliary body and peripheral choroid can be treated by local resection (partial lamellar sclerouvectomy). Local resection has theoretical advantages, but the surgical procedure is associated with potentially greater immediate complications. Enucleation is generally indicated for advanced melanomas that occupy most of the intraocular structures or have caused severe glaucoma. In addition, it is usually recommended for tumors that have invaded the optic nerve. The value of preenucleation radiotherapy in improving patient survival is unproved, although this technique seems reasonable in selected advanced tumors in which enucleation seems inevitable. Orbital exenteration is justified for advanced uveal melanomas with massive extraocular extension.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Current management of posterior uveal melanoma. 824 22

The reactivity spectrum of an anti-CALLA/CD10 monoclonal antibody for cutaneous melanoma was analysed by immunohistochemistry in a series of lesions of different Breslow thickness. Similar proportions of small primary tumours, advanced primary tumours and metastatic lesions were found to express CALLA/CD10 (31-47%). However the proportion of stained cells within a given lesion increased with tumour progression. Up to 23% of the advanced primary lesions (> 3.0 mm) showed 26-50% cells stained with the anti-CALLA/CD10 antibody and up to 14% of the metastatic lesions showed 76-100% stained cells. The expression of CALLA/CD10 was further analysed in 15 ocular melanoma lesions of different histiotype. All five spindle type lesions, three of six epitheloid and two of five mixed type lesions stained positively with the anti-CALLA/CD10 antibody. The percentage of stained cells within a given lesion varied from 30% to 100%. A total of 63% of the ocular melanomas and 38% of the cutaneous melanomas tested expressed CALLA/CD10. Experiments with cultured melanoma cell lines showed that the surface expression of CALLA/CD10 can be modulated in vitro by treatment with interleukin 2 (IL-2) and an adenosine 3',5'-cyclic monophosphate (analogue).
Melanoma Res 1993 Oct
PMID:Expression of CALLA/CD10 on human melanoma cells. 829 87


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>