Miguel N. Burnier

Cell Proliferation Profile of Five Human Uveal Melanoma Cell Lines of Different Metastatic Potential

Objective: The aim of this study was to establish a proliferation profile of uveal melanoma cell lines, using different methods, and to compare it with their previously determined metastatic potential (MP). Methods: Four human uveal melanoma and one transformed human uveal melanocytic cell line were ranked according to proliferation profiles. The proliferation profiles of the cell lines were compared to their MPs, which were previously determined from an immunosuppressed rabbit model. Results: Ranking of the cell lines using pulse labeling with tritiated thymidine was similar to the MP of the cell lines. Conclusion: The correlation between the proliferative rate of the uveal melanoma cell lines and their previously determined MP resulted in the proposal of a new classification scheme: high proliferation/high MP, low proliferation/low MP, and high proliferation/no MP. High proliferative capacity of a cell line did not necessarily confer MP; therefore, further cellular functions/adaptations must be required for tumor cell dissemination, survival, and growth at a metastatic site.

Histopathological study of 49 cases of keratoconus

Aims: Keratoconus is a bilateral and asymmetrical corneal ectasia. The pathophysiology of this disorder has yet to be fully elucidated. The purpose of our study was to document the prevalence of the most common morphological features of keratoconic corneas. Methods: A retrospective analysis of 49 cases diagnosed as keratoconus between 2001 and 2006 was undertaken. Histopathological reports were reviewed to obtain data such as age and gender. Specimens were fixed in 10% buffered paraformaldehyde solution for 24 h, bisected through the centre of the button, and embedded in paraffin. Sections were stained with haematoxylin and eosin (H&E) and periodic acid‐Schiff (PAS) for light microscopic examination. Results: The studied group was composed of 29 men and 20 women. Age at the time of the penetrating keratoplasty was 39 ± 14 years (mean ± standard deviation). Forty of the 49 specimens (82%) presented with epithelial thinning. Other common features of keratoconus included breaks in Bowmans layer in 35 (71%), compaction of the stromal collagen fibres in 31 (63%), and folds in Descemets membrane in 31 (63%) cases. Other less common histopathological findings were: presence of superficial iron deposits in 14 (29%), deep stromal scarring in 12 (24%), epithelial scarring in 11 (22%), endothelial cell loss in 11 (22%), and breaks in Descemets membrane in nine (18%) cases. Conclusions: Some of the histopathological findings associated with keratoconus are subtle. It is important to be aware of them in order to properly confirm the clinical diagnosis.

Orbital metastasis of urinary bladder carcinoma: a clinicopathologic report and review of the literature.

A 53-year-old male presented with a progressive mass of the left orbit. His medical history included an invasive carcinoma of the bladder diagnosed three weeks earlier. An orbital biopsy was performed and the diagnosis was that of an orbital metastasis of urinary bladder carcinoma. The patient developed widespread metastatic disease and unfortunately died one month after the diagnosis of orbital metastasis. Orbital metastasis of urinary bladder carcinoma is associated with a poor prognosis and is more frequently observed in older people. In addition, it is five times more prevalent in men than in women.

Ocular Gnathostomiasis in Brazil: A Case Report

Gnathostomiasis is a parasitic disease caused by nematode larvae ingestion of 15 known species of the genus Gnathostoma (one of the Gnathostomatidae family members). This parasite uses freshwater fish as a host and can infect - through the consumption of raw fish or their viscera - other animals such as dogs, cats, chickens, pigs, and humans. This parasitic disease, with humans acting as hosts, has been known since 1945 (India), and ocular complications have been known since 2004 (intravitreal; also described in India). Latin American countries, especially Mexico and Peru, have reported cases of the disease since 1970. The first dermatological case was reported in Brazil in 2009 (the individual had acquired the disease in Peru). This article describes the first reported ophthalmic case of the disease in Brazil and refers to a male patient, 30 years old, living in the municipality of Juruá, Amazonas State. The disease evolved within 30 days through a fistulized tumor in the inner corner of the lower eyelid. Following excision, the anatomical and histopathological examination revealed the presence of a different parasite species from other previously known genera.

Expression of SIRT2 and SIRT6 in Retinoblastoma

Purpose: SIRT2 and SIRT6 are members of the sirtuin family and are associated with cancer development and progression in certain tumours, but their expression in retinoblastoma has not been studied. The primary objective of our study was to determine the expression of SIRT2 and SIRT6 in human retinoblastoma cases. Methods: Eighteen formalin-fixed paraffin-embedded blocks of retinoblastoma cases from the Ocular Pathology Registry at the Henry C. Witelson Ocular Pathology Laboratory were obtained, classified and immunostained for SIRT2 and SIRT6 using mouse monoclonal antibodies. Results: Sixteen cases were poorly differentiated retinoblastoma cases. SIRT2 and SIRT6 were expressed in all cases of retinoblastoma although differences in the staining intensity were found between cases. SIRT2 and SIRT6 expression was also observed in various normal structures of the remaining ocular tissue. Conclusions: SIRT2 and SIRT6 are expressed in retinoblastoma, as well as in some normal ocular structures. While precise roles of these proteins must still be determined in retinoblastoma, their expression profiles suggest that further functional studies of both SIRT2 and SIRT6 should be pursued in this cancer.

Eyelid swelling as the only manifestation of ocular sarcoidosis.

Purpose: To describe a case of eyelid sarcoidosis without systemic manifestations with a three-year follow-up. Methods: A 73-year-old woman presented complaining of a one-year history of swelling and hyperemia in the right upper eyelid. To confirm the diagnosis, we performed an incisional biopsy of the eyelid. Results: Histopathological examination showed a non-caseating granulomatous process suggestive of sarcoidosis. After three years, the patient was asymptomatic and physical and laboratory examination showed no signs of systemic sarcoidosis. Conclusion: The histopathological exam was fundamental for the diagnosis.

Expression of focal adhesion kinase in uveal melanoma and the effects of Hsp90 inhibition by 17-AAG.

INTRODUCTION Focal adhesion kinase (FAK) is implicated in tumor progression and metastatic cascade, and has been shown to be overexpressed in a variety of human cancers. However, the role of FAK in human uveal melanoma (UM) is not well defined. The purpose of this study was to evaluate the expression of FAK in UM tumors and normal eyes, and to determine the effect of Hsp90 inhibition on FAK expression in UM cells. METHODS FAK expression was assessed in 39 UM specimens, FAK[pY397] expression was assessed in 51 UM specimens, and both FAK and FAK[pY397] expression were assessed in 20 normal eyes. The expression of FAK and FAK[pY397] was detected by Western blot in five UM cell lines after treatment with 10 μmol/L of 17-AAG. RESULTS FAK was positive in 87.2% and FAK[pY397] in 90% of UM specimens. Low FAK expression was detected in non-tumor structures and in normal eyes. The cell lines with the most proliferative, invasive phenotype (92.1, SP6.5 and MKT-BR) displayed high expression of FAK[pY397], and the levels of FAK and FAK[pY397] were decreased in the presence of 17-AAG starting with 24 h of exposure. CONCLUSION FAK and FAK[pY397] were overexpressed in human UM tumors compared to normal ocular tissue and high levels of FAK[pY397] were seen in the most aggressive UM cell lines. Hsp90 inhibition led to downregulation of FAK expression. We propose a role for FAK in the pathogenesis of UM. Future studies are needed to explore the use of Hsp90 inhibitors as a feasible approach for modulating FAK in UM.

Primary Pleomorphic Liposarcoma of the Orbit: A Case Report

To our knowledge, pleomorphic liposarcoma (PL) of the orbit has only been reported in the literature four times. This rarity makes it more difficult to diagnose and to treat in this clinical setting. A 62-year-old female presented with pruritus, edema, proptosis and diplopia 5 months OS. Imaging revealed an intraorbital mass displacing the globe, with infiltration into the sinus. The tumor was removed and the histological examination revealed a highly cellular tumor with heterogenous histology, with a few vacuolated cells and many malignant features. Immunohistochemistry allowed for the differential diagnosis, resulting in a diagnosis of PL of the orbit. The cells were immuno-positive for S-100 and negative for all other relevant markers. According to the literature, prognosis for this neoplasm is quite poor, and exenteration represents the best treatment option. The patient refused exenteration and radiation therapy, however, at 2 year follow-up, she remained recurrence-free.

Aberrant nuclear repressor coreceptor 1 localization in human retinoblastoma

Background/Aims: Nuclear receptor corepressor 1 (NCoR1) is a protein complex with diverse functions in development and tumorigenesis. We investigated the pattern of expression and histopathological correlation of NCoR1 in 41 retinoblastoma tumor samples, 1 retinoblastoma cell line (WERI-Rb-1) and human retinal progenitor cells (hRPCs). Methods: Tissue sections from 41 retinoblastoma cases, the retinoblastoma cell line WERI-Rb-1 and hRPCs were stained with rabbit polyclonal anti-NCoR1 H76 antibody. Percentage and intensity of staining were classified by an ocular pathologist from 0 to 3. The paired t test was used to test for differences. Results: In the nonneoplastic retina, NCoR1 was expressed mainly in cell nuclei. The retinoblastoma tumor cells similarly had nuclear NCoR1 but also had a higher level of cytoplasmic NCoR1 expression compared to all 3 normal retinal cell layers (p < 0.002). In contrast to the normal retina, NCoR1 was mainly expressed in the cytoplasm of the proliferating WERI-Rb-1 cells. This cytoplasmic expression pattern was also seen in the undifferentiated hRPCs. Conclusions: The aberrant cytoplasmic expression of NCoR1 in retinoblastoma appears to be associated with the proliferative and/or dedifferentiated properties of retinoblastoma. Further investigation into the role of NCoR1 in retinoblastoma may provide insight into how therapeutically inhibiting its nucleocytoplasmic shuttling may affect retinoblastoma tumor biology.

Pretreatment of RPE Cells with Lutein Can Mitigate Bevacizumab-Induced Increases in Angiogenin and bFGF

Purpose: To determine whether pretreatment of retinal pigmented epithelial (RPE) cells with lutein can affect the response of cells to bevacizumab therapy. Methods: One human RPE cell line (ARPE-19) was used for all experiments. The cells were treated with lutein in different concentrations (0.01, 0.1, 1, 10, or 100 μg/ml). After 24 h, all plates were treated with bevacizumab (0.25 mg/ml). Media were harvested 24 h later for sandwich ELISA-based angiogenesis arrays. A Quantibody Human Angiogenesis Array was used in order to quantify the secretion of the following 10 proangiogenic cytokines: angiogenin, ANG2, EGF, bFGF, HB-EGF, PDGF-BB, leptin, PIGF, HGF and VEGF. Results: Treatment with bevacizumab alone led to a significant decrease in VEGF, as well as a significant increase in angiogenin and bFGF. Pretreatment with 0.1 and 1.0 μg/ml of lutein led to significant decreases in both bFGF and angiogenin following treatment with bevacizumab compared to bevacizumab treatment alone. Lutein alone did not modify the secretion of proangiogenic cytokines. Conclusions: Pretreatment of human RPE cells in culture with specific doses of lutein prior to bevacizumab treatment mitigated the increase in bFGF and angiogenin caused by bevacizumab monotherapy.