Luteolin inhibits the proliferation, adhesion, migration and invasion of choroidal melanoma cells in vitro.

Choroidal melanoma is a devastating disease that causes visual loss and a high mortality rate due to metastasis. Luteolin, a potential anticancer compound, is widely found in natural plants. The aim of this study was to evaluate the antiproliferative, antiadhesive, antimigratory and anti-invasive effects of luteolin on choroidal melanoma cells in vitro and to explore its potential mechanism. Cell counting kit-8 (CCK-8) assays, 5-ethynyl-2'-deoxyuridine (EdU) assays, Cell adhesion, migration, and invasion assays were performed to examine the inhibitory effects of luteolin on cell cell viability, proliferation, adhesion, migration and invasion capacities, respectively. Considering the correlation between Matrix metalloenzymes and tumor metastasis, Enzyme-linked immunosorbent assays (ELISAs) were used to assess matrix metalloproteases MMP-2 and MMP-9 secretion. Western blotting was performed to detect p-PI3K P85, Akt, and p-Akt protein expression. The cytoskeletal proteins vimentin were observed with cell immunofluorescence staining. Luteolin can inhibit OCM-1 cell proliferation, migration, invasion and adhesion and C918 cell proliferation, migration, and invasion through the PI3K/Akt signaling pathway. Therefore, Luteolin may have potential as a therapeutic medication for Choroidal melanoma.

Coordinated targeting of MMP-2/MMP-9 by miR-296-3p/FOXCUT exerts tumor-suppressing effects in choroidal malignant melanoma.

Choroidal melanoma is the most common intraocular tumor in adults, and overexpression of matrix metalloproteinase-2 or matrix metalloproteinase-9 (MMP-2/MMP-9) is associated with angiogenesis and tumor metastasis of the choroidal malignant melanoma (CMM). This study aims to investigate the functions and mechanisms of microRNA or long non-coding RNA-targeted MMP-2/MMP-9 in CMM. We demonstrated that expressions of MMP-2/MMP-9 were increased in CMM tissues and C918 cells in comparison with normal choroidal melanocytes. Bio-informatics prediction and our experiments validated that MMP-2 and MMP-9 were simultaneously targeted by miR-296-3p and FOXC1 promoter upstream transcript (FOXCUT); the latter two exerted tumor-suppressing effects on CMM cells by inhibiting cell proliferation, cell cycle progression, migration, invasion, and induction of cell apoptosis. Furthermore, significant downregulations of miR-296-3p and FOXCUT were found in C918 cells compared with choroidal melanocytes from the unaffected eyes, and a positive correlation was observed between their levels in three cases of eye malignant melanomas. Our data indicated that MMP-2/MMP-9 was coordinately targeted by two non-coding RNAs, miR-296-3p and FOXCUT, which were decreased, and tumor-suppressing factors in CMM. Further study will show the possibility of developing them as therapeutic candidates for CMM.

Choroidal metastasis as a presenting manifestation of a lung adenocarcinoma with response to afatinib. / Metástasis coroidea como signo de presentación de un adenocarcinoma de pulmón con respuesta a afatinib.

CASE REPORT: We present the case of a 55-year-old man with a non-small cell lung adenocarcinoma, who presented with choroidal metastasis. The patient showed a decrease in visual acuity. His evaluation revealed unilateral choroidal metastasis secondary to carcinoma of the lung. The patient received afatinib with complete regression of choroidal metastasis after one year follow-up. DISCUSSION: Choroidal metastasis may be the initial sign of lung cancer. This case highlights the importance of a thorough systemic evaluation in patients with choroidal tumours. Afatinib was effective against choroidal metastasis of a lung adenocarcinoma with EFGR mutation.

Expression and prognostic value of putative cancer stem cell markers CD117 and CD15 in choroidal and ciliary body melanoma.

AIMS: The aim of the present study was to immunohistochemically investigate the expression and prognostic significance of putative cancer stem cell markers CD117 (c-kit), CD34, CD20 and CD15 in a cohort of patients with primary choroidal and ciliary body melanoma. METHODS: The immunohistochemical expression of these markers was evaluated using 3,3'-diaminobenzidine tetrahydrochloride (DAB) and 3-amino-9-ethylcarbazole (AEC) chromogens on paraffin-embedded tissue samples from 40 patients who underwent enucleation in the period from 1985 through 2000. Thirty-one patients had adequate tissue specimens for the analysis. RESULTS: CD117 overexpression was observed in 12 of the 31 samples (39%) when AEC chromogen was used and in 14 of 26 (54%) samples when DAB was used. CD15 positivity was seen in three out of 30 (10%) samples with AEC and in six out of 26 (23%) samples with DAB. CD20 and CD34 exhibited no positivity in the tested samples. During the average follow-up time of 8.7 years (range 0.5-22 years), 17 patients (55%) died due to metastatic disease. The Kaplan-Meier plots showed a significantly shorter overall and disease-free survival in CD117-positive patients when the AEC chromogen was used. CD15 expression was not associated with patients' survival. In multivariate analysis, patients expressing the CD117 AEC had 4.13 times higher risk of lethal outcome in comparison with CD117 AEC negative patients. CONCLUSIONS: Our retrospective cohort study has for the first time demonstrated a small proportion of CD15-positive uveal melanomas. CD117 AEC overexpression was associated with a worse outcome in patients with choroidal and ciliary body melanoma. Further studies should confirm the validity of these observations and their potential for targeted treatment modalities.

Simvastatin induces caspase-dependent apoptosis and activates P53 in OCM-1 cells.

Simvastatin is a cholesterol-lowering drug which exhibits numerous pleiotropic effects including anti-cancer activity. Yet, the anti-cancer effects in choroidal melanoma remain poorly characterized. Therefore, in this study, we investigated the effects of simvastatin on OCM-1 cells growth, apoptosis and cycle. Simvastatin showed an inhibitory effects on OCM-1 cells viability in dose-dependent (2-10 µM) and time-dependent (24-72 h) manner. Further study suggested that simvastatin-induced inhibition OCM-1 cells proliferation was associated with G1 phase arrest, decreased protein and mRNA expression of proliferation marker cyclin D1, cyclin E, cyclin dependent kinase (CDK)2 and increased expression of CDK inhibitory protein P21. In addition, simvastatin resulted in an increase in levels of reactive oxygen species (ROS) in OCM-1 cells and simvastatin significantly triggered apoptosis in OCM-1 cells, which was characterized by increased chromatin condensation, activation of caspase-9 and cleaved-caspase-3, increased expression mitochondrion-related apoptosis protein of P53, Bax and decreased expression of Bcl2 and iASPP. Collectively, our study demonstrated that simvastatin can efficiently inhibit proliferation and induce apoptosis in OCM-1 cells.

A phase II study of gefitinib in patients with metastatic melanoma.

Gefitinib is an inhibitor of the epidermal growth factor receptor, which is frequently expressed on both choroidal and nonchoroidal melanoma cells. We evaluated the clinical efficacy of gefitinib in patients with metastatic melanoma. Patients with stage IV or unresectable stage III melanoma and Zubrod performance status of less than or equal to 2 were eligible. Previous systemic treatment for metastatic disease was required. The dose of oral gefitinib was 250 mg administered daily, and tumor response was evaluated every 6 weeks. Forty-six patients with nonchoroidal melanoma and six with choroidal melanoma were treated, and 48 were evaluable for response. The median age was 62.5 years. Forty-one patients (79%) had stage M1c disease. There were no drug-related grade 4 or 5 adverse events, and fatigue was the only grade 3 adverse event that occurred in more than 5% of patients. Two patients (4%) had partial responses and 13 patients (27%) had disease stabilization. The two responders had a median duration of response of 10.9 months. The median overall progression-free survival was 1.4 months and the median overall survival was 9.7 months. Among the patients with sufficient tissues obtained before and 6 weeks after starting gefitinib administration, there were no notable trends in the changes of the tumoral expression of p-ERK1/2, p-AKT, PAK1, and serum levels of vascular endothelial growth factor or IL-8 with treatment. We concluded that gefitinib was well tolerated but had minimal clinical efficacy as a single-agent therapy for unselected patients with metastatic melanoma.

Expression and prognostic significance of iNOS in uveal melanoma.

Uveal melanoma (UM) is the most common primary intraocular tumor in adults. Disease metastasis occurs in half of the patients and is uniformly fatal despite systemic therapy. Inducible nitric oxide synthase (iNOS) is associated with disease progression in various malignancies including cutaneous melanoma. In this retrospective cohort, we examined the prognostic value of iNOS in UM by performing immunohistochemistry on paraffin-embedded sections of primary tumors (90 patients) and matched primary and metastatic hepatic tumors (19 patients) with complete histopathological and clinical data. We show that iNOS is expressed in UM (57% of the patients) and high iNOS levels significantly (p = 0.04; hazard ratio (HR) = 2.3) predict disease-specific survival (DSS) as assessed by Kaplan-Meier analysis and univariate Cox's proportional hazards regression model. Furthermore, high iNOS expression in the UM primary tissue was significantly associated with metastatic disease and vice versa. Expression of iNOS in hepatic metastases significantly (p = 0.02) predicted a shortened survival as assessed by Kaplan-Meier analysis. However, iNOS did not appear to be a significant (p = 0.16; HR = 1.9) factor in the multivariate Cox's regression analysis performed together with the clinical parameters tumor diameter, tumor cell type, and tumor location in which only tumor diameter predicted DSS. In conclusion, iNOS predicts DSS in UM and may play a role in disease progression but it is not an independent prognostic factor.

Role of the Yes and Csk tyrosine kinases in the development of a pathological state in the human retina.

Amplification and a cloning of fragments of genes of human retina tyrosine kinases, the nucleotide sequences of which feature a high homology to the gene families of the Yes and Csk tyrosine kinases, and a cloning of the complete coding sequence of the cDNA of the Csk tyrosine kinase gene of the human lymphocytes have been carried out. It has been established that this sequence contains 1,624 bp and encodes a protein that, with a 99% homology, corresponds to the human tyrosine kinase. A comparative analysis of the nucleotide sequences of the full-size cDNA of the Csk tyrosine kinase of the lymphocytes of healthy donors and of patients with an eye choroidal melanoma has shown that a risk of development of an eye choroidal melanoma can be estimated by the frequency of occurrence of a mutant allele in the 10th exon.

Expression of COX-2 and prognostic outcome in uveal melanoma.

PURPOSE: The expression of cyclooxygenase-2 (COX-2) and its prognostic value in uveal melanoma was examined. METHODS: Paraffin-embedded sections from 32 clinicopathologically well-characterized cases of primary uveal melanoma were immunohistochemically stained for COX-2. COX-2 expression was evaluated in terms of both the intensity and the extent of staining for each tumor. A COX-2 score encompassing both intensity and extent was also calculated for each specimen. RESULTS: 29 specimens (90.6%) contained moderate or intense positive immunoreactivity for COX-2. A statistically significant association (p<0.05) between COX-2 expression (intensity and score) and metastatic death was established. CONCLUSION: Upregulation of COX-2 expression appears to be associated with poor prognosis in uveal melanoma.

[Cloning and analysis of coding cDNA sequence of human lymphocyte Csk tyrosine kinase under normal conditions and in choroidal melanoma].

The main function of Csk tyrosine kinases is phosphorylation of the C-terminal part of Srk tyrosine kinases as a mechanism of their downregulation. A decrease in the expression of csk gene results in the enhancement of Srk tyrosine kinase activity. In this study, cDNA containing the full coding sequence of the human leukocyte Csk tyrosine kinase gene has been cloned. The protein encoded by a a 1624-bp cDNA fragment has 99% homology to human Csk tyrosine kinase. A comparative sequence analysis of full-length cDNAs for Csk tyrosine kinase of normal lymphocytes and lymphocytes of patients with choroidal melanoma revealed a nucleotide substitution in dexon 10 of the gene, which appears to be of diagnostic significance. It has been shown that the risk of choroidal melanoma correlated with the frequency of this allele.

The effect of ultraviolet radiation on choroidal melanocytes and melanoma cell lines: cell survival and matrix metalloproteinase production.

BACKGROUND: Ultraviolet radiation (UVR) can induce DNA damage and regulate the expression of factors important for tumour growth and metastasis, including matrix metalloproteinases (MMPs). Epidemiological studies suggest that chronic UVR exposure, especially during early adulthood, may be a risk factor in patients with choroidal melanoma. However, the effects of UV(R)-B on human choroidal melanocyte survival and growth are unknown. In this study, we investigated if UV(R)-B affected the in vitro survival, growth and MMP production of choroidal melanocytes and melanoma cells. METHODS: Cultures of primary choroidal melanocytes and melanoma cell lines (OCM-1 and OCM-8) were exposed to UV(R)-B (0-30 mJ/cm(2)). The cell morphology and growth were examined, and cell viability was assessed using an MTT assay. Gelatin zymography was used to assess the enzymatic activity for MMP-2 and -9 in conditioned media following UV(R)-B treatment. RESULTS: UV(R)-B > or =20 mJ/cm(2) was cytotoxic for choroidal melanocytes. Cytotoxic doses of 5 to 10 mJ/cm(2) were found for OCM-8 and OCM-1 melanoma cell lines. Low levels of UV(R)-B (2.5 and 3.5 mJ/cm(2)) significantly reduced melanoma cell viability after 48 h, although melanocyte viability was not affected by doses of UV(R)-B <10 mJ/cm(2). Conditioned media from melanoma cells and melanocytes displayed pro-MMP-2 activity independent of UV(R)-B. Control and UV(R)-B-treated OCM-1 cells secreted active MMP-2 up to 72 h. Pro-MMP-9 activity was seen from 36 h for control and UV(R)-B-treated OCM-1 and OCM-8 cells. CONCLUSIONS: Melanocytes appeared more resistant to physiological doses of UV(R)-B than melanoma cells; the potential of melanocytes to initially survive DNA damage following UV(R)-B exposure may be relevant to the subsequent transformation of melanocytes to melanomas. Although UV(R)-B did not induce the production and/or activation of MMP-2 and -9 in melanocytes or melanoma cells, we are currently investigating whether DNA damage-response genes such as p53 and p21 can be regulated following UVR exposure, and whether they are important for choroidal melanoma development.

Detection of BRAF gene mutation in primary choroidal melanoma tissue.

Numerous BRAF mutations have been detected in melanoma biopsy specimens and cell lines. In contrast, several studies report lack of BRAF mutations in uveal melanoma including primary and metastatic choroidal and ciliary body melanomas. To our knowledge, for the first time, here we report a case of choroidal melanoma harboring the BRAF mutation (V600E). The activation of RAF/MEK/ERK pathway, although independent of BRAF mutation, was reported in uveal melanoma. The presence of V600E mutation indicates that the RAF/MEK/ERK pathway, in addition to cutaneous melanoma progression, may play a role in the choroidal melanoma development.

[In vitro study on inhibition of human choroidal melanoma OCM-1 cell line by arsenic trioxide].

OBJECTIVE: To investigate the effects and mechanisms of arsenic trioxide (ATO) on human choroidal melanoma cell line OCM-1. METHODS: OCM-1 cells were cultured with 0.75 to 24.00 micromol/L arsenic trioxide for various durations, then cell viability was measured by MTT assay. The cell necrosis and apoptosis rates were observed by flow cytometry. The morphological changes of the cells were examined by electron microscopy. Glutathione peroxidase (GSH-Px) activities were tested. Mitochondrial membrane potential (MMP) was detected by confocal microscopy. RESULTS: Growth of OCM-1 cells was inhibited by ATO at concentrations of (1.5 to 24.0) micromol/L. However, there was no effect of 0.75 micromol/L ATO on the growth of OCM-1 cells. The inhibition showed both dose and time dependent effects (P < 0.05). The IC(50) was 16.8 micromol/L at 24 h. Flow cytometry analysis showed a positive correlation between the rate of cell necrosis and apoptosis and the concentration of ATO. The cell necrosis rates were higher than the cell apoptosis rates at various concentrations of ATO. OCM-1 cells cultured with ATO showed the classic morphologic characteristics of necrosis and apoptosis. GSH-Px activities and MMP decreased in a dose dependent manner. CONCLUSION: ATO inhibits the growth of OCM-1 cells. The mechanism of this effect is that ATO inhibits the GSH-Px activities, decreases the MMP and impairs mitochondrial energy synthesis, which induces necrosis and apoptosis of human choroidal melanoma COM-1 cells eventually.

Expression of thymidine phosphorylase in choroidal malignant melanoma associated with neovascular glaucoma.

Reported herein is a case of 62-year-old man who complained of blurred vision and ocular pain in his right eye. The patient was diagnosed with choroidal melanoma complicated by neovascular glaucoma (NVG) and total retinal detachment, and he underwent enucleation of the eye. The isolated tumor was 2.5 x 2.5 cm in size. It was accompanied by intratumoral calcification, and consisted of epithelioid and spindle melanoma cells. There were a variety of microvessels in the stroma of the iris. The expression of thymidine phosphorylase (dThdPase), an angiogenic factor, was examined immunohistochemically. Cytoplasmic immunoreactivity for dThdPase was more prominent in the epithelioid cells than in spindle tumor cells. Another case of choroidal melanoma without NVG had less marked immunoreactivity. These results suggest that the production of dThdPase by melanoma cells correlates with the pathogenesis of NVG.

Inhibition on telomerase activity and cytotoxic effects by cisplatin in cultured human choroidal melanoma cells.

PURPOSE: To study the changes of telomerase activity and cytotoxic effects by Cisplatin; cis-dichlorodiamine platinum (CDDP) in cultured human choroidal melanoma. MATERIAL AND METHODS: The primary cultured human choroidal melanoma cells were cultured in the presence and absence of CDDP with different concentration and time respectively. The toxic effects were evaluated by MTT and the level of telomerase was detected by PCR-ELISA assay. And the relationship between telomerase activity and cytotoxic effects were analyzed by a correlation analysis. RESULTS: Following the increase of the concentration and the time of CDDP, gradually repressed telomerase activity was detected in cultured cells. Meanwhile, the restrain rate of the cells increased. The telomerase activity at 24 h and 1 microgram/ml was repressed significantly compared with the control cells. However, the appearance of cell death lagged behind the decreasing of telomerase. CONCLUSIONS: CDDP is an effective telomerase inhibitor in cultured choroidal melanoma cells of human eyes, which presents concentration and time dependency and can cause the death of cultured cells.

Relationship between expression of topoisomerase II isoforms and chemosensitivity in choroidal melanoma.

Choroidal melanoma has a high mortality rate and responds poorly to existing chemotherapy, but unexpected ex vivo sensitivity of a subset of these tumours to topoisomerase II inhibitors has been noted. Since chemoresistance may be mediated by the molecular phenotype of tumours, immunohistochemistry has been used to study the expression of both isoforms of topoisomerase II (alpha and beta) in 29 choroidal melanomas for which chemosensitivity assay data for doxorubicin or mitoxantrone are also available. Of these, eight tumours were topoisomerase II beta-positive and 11 were topoisomerase II alpha-positive. Recent studies showing genetic abnormality (often monosomy of chromosome 3) in choroidal melanoma suggest that loss of immunostaining could be due to genomic loss rather than down-regulation of topoisomerase II beta in these tumours. There was no convincing excess of anthracycline resistance in the topoisomerase II beta-negative group. Addition of topoisomerase II alpha, MDR1 (11/17 positive), LRP (16/28 positive), and MRP (5/29 positive) data in multivariate analysis did not reliably predict sensitivity or resistance. Vincristine chemosensitivity showed no relation to MDR1, LRP or MRP in 18 tumours tested. While it is possible that some tumours which do express topoisomerase II beta may respond to anthracyclines, the molecular basis of resistance or sensitivity to anthracyclines or vincristine in uveal melanoma is complex and remains incompletely understood.

[Value of serologic tumor tests in malignant melanoma of the choroid]. / Zur Wertigkeit serologischer Tumortests beim malignen Melanom der Aderhaut.

In about 350 patients with malignant melanoma of the choroid 32 serological tumor tests, specific as well as nonspecific, were carried out. Significant differences were found in: leukocyte adherence inhibition test (LAI), electrophoresis mobility test (EMT), carcinoembryonic antigen (CEA), acid alpha-1-glycoprotein (AGP), immunoglobin G, vitamin A, copper, and magnesium. For early diagnosis of malignant melanoma of the choroid the LAI test, together with the examination of immunoreactive lymphocyte subpopulations (helper and suppressor cells) proved to be the most valuable.

Tyrosinase activity in human ocular malignant melanoma.

We examined tyrosinase activity in pigmented specimens from three cases of ocular malignant melanoma. Tissue (cholate-trypsin-treated) extract was prepared in cholate-phosphate buffer by homogenization, centrifugation, trypsin digestion, and hydroxylapatite column chromatography. Tyrosinase activity was spectrophotometrically assayed as dopa (L-3,4-dihydroxylphenylalanine) oxidase activity. Tyrosinase activity was detected in the cholate-trypsin-treated extracts. Enzyme activity was inhibited by phenylthiourea but not by 3-iodo-tyrosine. The enzyme was inactivated when extract was preheated or digested with pronase. We believe that our findings confirm the presence of tyrosinase activity in ocular malignant melanoma.