Angiogenesis and screening in uveal melanoma

This thesis describes several topics on angiogenesis and screening in uveal melanoma, the most frequent eye tumour in adults. The expression of vascular endothelial growth factor and other angiostimulating factors in this tumour are described. In a second part, the use of different screening tests in screening for metastases of uveal melanoma is investigated.Leids Universitair Medisch CentrumThe Netherlands Cancer Institute (Koningin Wilhelmina Kanker Fonds)Vasculair en neoplastisch oogheelkundig onderzoe

Dumbbell-shaped dermoid cysts

Ophthalmic researc

Dumbbell-shaped dermoid cysts

Ophthalmic researc

Epistaxis or epiphora as a sign for extension of a conjunctival melanoma. A series of six patients with nasolacrimal recurrence

Purpose To characterise malignant conjunctival melanomas with extension and recurrence in the nasolacrimal system. Methods Localisation of the primary tumour and recurrences of 210 conjunctival melanomas treated in The Netherlands were reviewed for orbital and nasal tumours (1978-2008). Based of these cases and literature data, characteristics for nasolacrimal system extension and metastasis were reviewed. Results Six patients (3%) showed a recurrence of the primary conjunctival melanoma in the nasolacrimal system. Two of the six primary tumours were limbal tumours; the other four were diffuse tumours involving the fornix. In all six patients, the primary conjunctival melanomas were associated with primary acquired melanosis. During the follow-up period (11.6 +/- 3 years, range 3.4-28.5 years, median 8.7 years) two patients developed metastases and died. Conclusions Patients should be advised to contact their treating ophthalmologist in the case of symptoms of epiphora, nose obstructions and epistaxis, especially non-bulbar and diffuse cases associated with primary acquired melanosis.Ophthalmic researc

Angiogenic profile of uveal melanoma.

Item does not contain fulltextUveal melanoma develops in one of the most capillary-rich tissues of the body and is disseminated hematogenously. Knowledge of the nature and the spatiotemporal expression of angiogenic factors in uveal melanoma is essential to the development of new treatment strategies, especially with regard to improving survival. In this study, we measured the angiogenic potential of several angiogenic factors in different uveal melanoma cell lines, in an in vivo model, and in primary tumor material from patients with melanoma. Most uveal melanoma cell lines expressed vascular endothelial growth factor (VEGF)-A (isoforms 121, 165, 189), VEGF-B, VEGF-C, VEGF-D, and basic fibroblastic growth factor (b-FGF) to various extents. The expression of VEGF-A 121 was always higher than that of the other VEGF-A isoforms, suggesting that VEGF-A 121 is the most abundant VEGF-A isoform. All experimentally induced tumors expressed VEGF-A, VEGF-B, VEGF-C, VEGF-D, and basic fibroblastic growth factor (b-FGF). Similarly, significant amounts of mRNA for VEGF-B, VEGF-C, VEGF-D, and b-FGF were detected in uveal melanoma material from patients. In contrast, VEGF-A mRNA (121, 165, 189) was low (9/28) or not detectable in the tumor samples. The synthesis of VEGF-A 165 and b-FGF protein by various cell lines was measured by enzyme-linked immunosorbent assay (ELISA). Most uveal melanoma cell lines, but not normal melanocytes, strongly synthesized and secreted VEGF-A 165 and b-FGF during cell culture. Our data suggest that the expression of (lymph) angiogenic factors may play a causal role in the angiogenesis and progression of uveal melanoma and distant metastasis

S-100B protein and melanoma inhibitory activity protein in uveal melanoma screening. A comparison with liver function tests.

Item does not contain fulltextAIM: Our purpose was to determine whether S-100B or melanoma inhibitory activity (MIA) concentrations in the serum of patients with large uveal melanomas were better markers for the presentation of metastases than liver function tests. We also investigated whether increased marker levels were related to known clinical and histopathological prognostic parameters. METHODS: Total S-100B (A1B + BB) and MIA concentrations were measured in the sera from 104 patients with uveal melanoma prior to enucleation and in the sera from 50 healthy controls. Concentrations were also determined in the sera from 30 patients with known uveal melanoma metastases. Liaison Sangtec 100, an automated immunoluminometric assay measuring the total S-100B, and Roche MIA ELISA were used to quantify these proteins in serum. Results were compared with liver function tests [alkaline phosphatase, lactate dehydrogenase (LD), aspartate aminotransferase, alanine aminotransferase and gamma-glutamyl transpeptidase]. RESULTS: The mean S-100B and MIA concentrations were significantly higher in patients with metastases compared to melanoma patients without metastases. At the time of enucleation, S-100B and MIA were not prognostic for metastases in uveal melanoma, but S-100B and LD were the best tests to predict the occurrence of metastatic disease during the follow-up period. CONCLUSIONS: In our study, the S-100B and MIA serum concentrations were not correlated with any tested established prognostic parameter. S-100B and LD showed better performance in identifying melanoma metastases than gamma-glutamyl transpeptidase and MIA. A prospective follow-up study is needed to evaluate S-100B and MIA in identifying early micrometastasis in uveal melanoma

Vascular endothelial growth factor a in eyes with uveal melanoma.

Item does not contain fulltextOBJECTIVES: To determine the presence of vascular endothelial growth factor A (VEGF-A) in the aqueous humor of eyes with uveal melanoma and to identify its source. METHODS: The VEGF-A concentrations were determined in aqueous humor samples obtained after enucleation from 74 eyes with untreated uveal melanoma and from 8 eyes with treated uveal melanoma. Patient survival and clinical and histopathological tumor variables were compared. In situ hybridization, Western blot analysis, and enzyme-linked immunosorbent assay were used to determine expression of VEGF-A in tumor tissue and in overlying retina. RESULTS: Aqueous VEGF-A concentrations ranged from 18 to 826 pg/mL in 74 untreated eyes, while concentrations in 30 control eyes were significantly lower (median, 50.1 pg/mL) (P<.001). Concentrations in 8 treated eyes were much higher (median, 364 pg/mL). In situ hybridization on tissue sections and Western blot analysis and enzyme-linked immunosorbent assay on tissue extracts revealed VEGF-A in uveal melanoma tissue and in retinal tissue. CONCLUSIONS: Uveal melanoma is associated with increased concentrations of VEGF-A in aqueous humor. Aqueous VEGF-A concentration correlates with largest basal tumor diameter and with the tumor height. In eyes with uveal melanoma, tumor and retinal tissues are sources of VEGF-A

Whole-body bioluminescent imaging of human uveal melanoma in a new mouse model of local tumor growth and metastasis.

Item does not contain fulltextPURPOSE: Human uveal melanoma develops in one of the most capillary-rich tissues of the body and has a pure hematogenous dissemination. Radiodiagnostic examinations, such as ultrasonic diagnostic resonance imaging and chest radiographs plus liver enzyme studies in blood, are methods used to detect liver and other distant metastases in patients. Nevertheless, the mortality rate is high, because of the frequent occurrence of metastases and the lack of systemic therapy. Therefore, the development of novel anticancer strategies is urgent, and more sensitive and less invasive methods of detecting and monitoring in vivo tumor growth and metastatic disease in cancer models are needed. METHODS: A luciferase (Luc)-positive human uveal melanoma cell line (OCM-1 FRT/luc) was established. Tumor cells were inoculated into the anterior chamber of murine eyes for induction of orthotopic growth or into the left heart ventricle to mimic hematogenous micrometastatic spread. Development of metastases and tumor growth was monitored weekly by whole-body bioluminescent reporter imaging (BLI). RESULTS: Injection of cancer cells into the anterior chamber of the eye of mice closely mimicked orthotopic tumor growth of uveal melanoma. Tumor progression could be quantitatively monitored 3 weeks after inoculation of 10(5) OCM-1 FRT/luc cells. Of the mice injected, 83% exhibited a detectable tumor within 5 weeks. Intracardiac injection of tumor cells resulted in metastatic growth, especially in bone. Mice had bone (maxillofacial region and femora) and visceral (lung and mediastinum) metastases after 4 to 6 weeks. OCM-1 FRT/luc cells may also have a propensity to colonize the eye after intracardiac inoculation. CONCLUSIONS: BLI enables continuous quantitative monitoring in the same animal of growth kinetics for each tumor and its metastases. This model will accelerate the understanding of the pathogenesis and treatment of uveal melanoma and metastasis