bromochloroacetic-acid and Uveal-Neoplasms

The long-range goal of our research is to develop intervention strategies based on newly discovered biologic mechanisms responsible for the invasive dissemination of metastatic uveal melanoma. To accomplish this goal, we have focused on the biologic relevance of novel marker proteins contributing to the uveal melanoma metastatic phenotype. The expression of vimentin intermediate filaments (IFs), a mesenchymal marker, is typical of melanomas, whereas carcinomas typically express keratin IFs, which are markers for epithelia. Thus, cells that coexpress both IFs are regarded as "interconverted" in that they display both mesenchymal and epithelial phenotypes. Although the biologic functions of IFs have remained enigmatic, there is substantial support to suggest that the significance of vimentin/keratin coexpression is linked with poor patient outcome in cutaneous melanoma. Our data demonstrate that human uveal melanoma cell lines (isolated from primary choroidal or ciliary body melanomas and from foci of metastatic uveal melanoma to the liver), which contain predominant populations of cells that coexpress vimentin/keratins 8 and 18 (keratins 8,18) IFs, were 6-fold more invasive through collagenous extracellular matrices in vitro, compared with uveal melanoma cells expressing vimentin only, and were 8- to 13-fold more invasive than normal uveal melanocytes. Colocalization of vimentin/keratins 8,18 in cell cultures was corroborated by immunohistochemistry in histologic sections of tumors from which the cell lines were derived. Minor populations of these cells also coexpressed keratins 13 and 17. Experimental down-regulation of the predominant keratins 8,18 in the interconverted cells, using 16-mer antisense oligonucleotides, resulted in a significant decrease in the migratory ability of the cells-similar to levels achieved by cells positive only for vimentin. These findings provide justification for additional studies of the association between coexpression of IFs vimentin/keratins 8,18 and uveal melanoma metastasis.

Topics: Antisense Elements (Genetics); Biomarkers, Tumor; Choroid Neoplasms; Ciliary Body; Forecasting; Humans; Intermediate Filament Proteins; Keratins; Liver Neoplasms; Melanoma; Neoplasm Invasiveness; Phenotype; Time Factors; Tumor Cells, Cultured; Uveal Neoplasms

To evaluate the distribution of the PAX8 transcription factor protein in ocular tissues and to investigate if immunohistochemical stains for this biomarker are useful in the diagnosis of intraocular tumors.. Observational case series.. Excision and cytologic analysis specimens of 6 ciliary body epithelial neoplasms, 2 iris epithelial neoplasms, 3 retinal pigment epithelial neoplasms, 3 intraocular medulloepitheliomas, 15 uveal melanomas, and 5 uveal melanocytomas.. Hematoxylin-eosin and PAX8 immunohistochemical stains were performed on all specimens. In appropriate cases, bleached preparations and other immunohistochemical stains, including AE1/AE3 cytokeratin, Lin28A, and CD45, were performed.. Distribution of PAX8 expression in normal and neoplastic tissue.. Strong nuclear PAX8 expression was observed in the normal corneal epithelium, iris sphincter pupillae muscle, iris pigment epithelium and dilator muscle complex, nonpigmented and pigmented epithelia of the ciliary body, lens epithelium, and a subset of retinal neurons. The normal retinal pigment epithelium and uveal melanocytes did not stain for PAX8. The ciliary body epithelial and neuroepithelial tumors (adenoma, adenocarcinoma, and medulloepithelioma) showed uniform strong nuclear PAX8 immunoreactivity. All melanocytic tumors (iris melanoma, ciliary-choroidal melanoma, and melanocytoma) and retinal pigment epithelial neoplasms showed negative results for PAX8. A subset of tumor-associated lymphocytes, most prominent in uveal melanoma, showed positive results for PAX8. The uniformity of the PAX8 staining was superior to the variable cytokeratin staining in the ciliary epithelial neoplasms and the variable Lin28A staining in malignant medulloepithelioma. The veracity of PAX8 staining was equally as robust on cytologic analysis and open-flap biopsy specimens of ciliary epithelial and iris epithelial neoplasms, melanocytoma, and melanoma.. PAX8 has proven to be a very useful diagnostic marker in a select group of adult intraocular tumors, and we highly recommend its inclusion in diagnostic antibody panels of morphologically challenging intraocular neoplasms.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Biomarkers, Tumor; Ciliary Body; Eye Neoplasms; Female; Humans; Immunohistochemistry; Iris Neoplasms; Keratins; Leukocyte Common Antigens; Male; Melanoma; Middle Aged; Neoplasms, Glandular and Epithelial; PAX8 Transcription Factor; Retinal Neoplasms; Retinal Pigment Epithelium; RNA-Binding Proteins; Uveal Neoplasms

To define the maturational sequence of 3 infantile intraocular medulloepitheliomas.. Retrospective clinicohistopathologic and immunohistochemical study.. Immunoreactivity of paraffin sections for CRX (cone-rod homebox transcription factor) and NeuN (biomarker for neuronal differentiation) were investigated together with other biomarkers, including S100, glial fibrillary acidic protein, epithelial membrane antigen, and various cytokeratins.. Three infants (aged 1, 6, and 8 months) had iris neovascularization, 2 had anterior ciliary body tumors, and 1 a posterior tumor associated with a retinochoroidal coloboma. Each tumor displayed a premedullary monolayer of cuboidal epithelium that was S100(+), NeuN(-), and CRX(-) and that transitioned into a multilaminar medullary epithelium forming neurotubules with adluminal cells that were CRX(+). NeuN first appeared in ablumenal neurotubular cells in 1 tumor and was also discovered among neuroblast-appearing cells in another. The third tumor associated with a coloboma was CRX(-) and NeuN(-).. A simple premedullary epithelial monolayer appears to be the fundamental source for the tumor and its multilaminar medullary epithelium. CRX(+) and NeuN(+) cells within the multilayered medullary layer approximate expression patterns similar to those found in retinal development and differentiation. Discovery of these biomarkers in the neoplastic ciliary epithelium in a small number of tumors indicates preliminarily that the most anterior layers of the optic cup have a retained retinal and neuroglial differentiation potentiality. The third case was CRX(-) and NeuN(-) and possibly arose from embryonic pigment epithelium at the edge of the retinochoroidal coloboma. These immunohistochemical findings offer histogenetic and potential diagnostic insights.

Topics: Antigens, Nuclear; Biomarkers, Tumor; Choroid; Ciliary Body; Coloboma; Female; Glial Fibrillary Acidic Protein; Homeodomain Proteins; Humans; Immunoenzyme Techniques; Infant; Infant, Newborn; Keratins; Male; Mucin-1; Nerve Tissue Proteins; Neuroectodermal Tumors, Primitive; Retina; Retinal Neoplasms; Retrospective Studies; S100 Proteins; Trans-Activators; Uveal Neoplasms

Mesectodermal leiomyoma of the ciliary body is a rare tumor with, to our knowledge, only 15 cases reported in the literature. It has a neural histopathologic appearance and a presumed origin from neural crest.. Case report.. Two cases of mesectodermal leiomyoma with histopathologic and immunohistochemical confirmation are reported.. For the second time, we were able to demonstrate expression of neural immunohistochemical markers in this tumor.

Topics: Actins; Adult; Antigens, Neoplasm; Biomarkers, Tumor; Ciliary Body; Female; Glial Fibrillary Acidic Protein; Humans; Immunohistochemistry; Keratins; Leiomyoma; Male; Melanoma-Specific Antigens; Middle Aged; Muscle Proteins; Neoplasm Proteins; Nerve Tissue Proteins; Uveal Neoplasms; Vimentin

The molecular analysis of cancer has benefited tremendously from the sequencing of the human genome integrated with the science of bioinformatics. Microarray analysis technology has the potential to classify tumors based on the differential expression of genes. In the current study, a collaborative, multidisciplinary approach was utilized to study the molecular determinants of human uveal melanoma invasion and metastasis. Uveal melanoma is considered the most common primary intraocular cancer in adults, resulting in the death of approximately 50% of patients affected. Unfortunately, at the time of diagnosis, many patients already harbor microscopic metastases, thus underscoring a critical need to identify prognostic markers indicative of metastatic potential. The investigative strategy consisted of isolating highly invasive vs. poorly invasive uveal melanoma cells from a heterogeneous tumor derived from cells that had metastasized from the eye to the liver. The heterogeneous tissue explant MUM-2 led to the derivation of two clonal cell lines: MUM-2B and MUM-2C. Further morphological and functional analyses revealed that the MUM-2B cells were epithelioid, interconverted (expressing mesenchymal and epithelial phenotypes) highly invasive, and demonstrated vasculogenic mimicry. The MUM-2C cells were spindle-like, expressed only a vimentin mesenchymal phenotype, poorly invasive, and were incapable of vasculogenic mimicry. The molecular analysis of the MUM-2B vs. the MUM-2C clones resulted in the differential expression of 210 known genes. Overall, the molecular signature of the MUM-2B cells resembled that of multiple phenotypes--similar to a pluripotent, embryonic-like genotype. Validation of select genes that were upregulated and down-regulated was conducted by semiquantitative RT-PCR measurement. This study provides a molecular profile that will hopefully lead to the development of new molecular targets for therapeutic intervention and possible diagnostic markers to predict the clinical outcome of patients with uveal melanoma.

Topics: Adult; Down-Regulation; Genotype; Humans; Immunohistochemistry; Keratin-8; Keratins; Male; Melanoma; Microscopy, Fluorescence; Models, Biological; Neoplasm Invasiveness; Neoplasm Metastasis; Oligonucleotide Array Sequence Analysis; Prognosis; Reverse Transcriptase Polymerase Chain Reaction; Tumor Cells, Cultured; Up-Regulation; Uveal Neoplasms; Vimentin

Human uveal melanoma disseminates initially and preferentially to the liver. This study describes the relationship between the expression of the c-met proto-oncogene (receptor for hepatocyte growth factor/scatter factor (HGF/SF)) in interconverted uveal melanoma cells (co-expressing vimentin and keratin intermediate filaments) and the regulation of their motogenic response to HGF/SF, a key step in local invasion and targeted dissemination to the liver. Expression of c-met in uveal melanoma cell lines correlates with both the appearance of an interconverted phenotype and invasive ability (measured in vitro). Using chemotactic checkerboard analysis, the greatest motogenic response to HGF/SF was achieved by invasive, interconverted, c-met-positive uveal melanoma cells. C-met was observed histologically in a uveal melanoma containing interconverted cells but was absent in a tumor composed of non-interconverted cells (vimentin positive/keratin negative). The c-met ligand, HGF/SF, although not expressed by uveal melanoma cell lines, was localized in tissue sections of primary uveal melanomas and metastatic melanoma to the liver. In the primary tumor, staining for HGF/SF was most intense at the level of the choriocapillaris, a finding that is significant because 1) highly remodeled neovascular loops and networks, which appear in tumors likely to disseminate, can be traced to the choriocapillaris and the draining vortex veins and 2) HGF/SF plays a role in tumor angiogenesis. Foci of metastatic melanoma to the liver stain diffusely for HGF/SF. Regulation of the uveal melanoma interconverted phenotype by HGF/SF may play an important role in the dissemination of this tumor.

Topics: Blotting, Northern; Cell Movement; Hepatocyte Growth Factor; Humans; Immunohistochemistry; Keratins; Liver Neoplasms; Melanoma; Microscopy, Confocal; Models, Biological; Prognosis; Proto-Oncogene Mas; Proto-Oncogene Proteins c-met; Tumor Cells, Cultured; Uveal Neoplasms; Vimentin

A group of 52 patients with malignant uveal melanoma treated by primary enucleation in 1977-1979 was studied to determine the frequency of immunoreactivity for cytokeratins (CK) in primary and metastatic melanoma, the CK types present, and the prognostic significance of CK expression. By immunohistochemistry, monoclonal antibody (MAb) V9 to vimentin reacted with all 52 formalin-fixed, paraffin-embedded primary tumors and all 31 metastases from 11 patients. MAb CAM 5.2 to CK 8 and 18 reacted with 20 and MAb CY-90 to CK 18 with 25 primary melanomas, whereas MAb KS-B17.2 and MAb CK5 to CK 18 labeled 8 and 6 tumors, respectively. Antibodies to CK 13 and CK 19 each labeled single cells in one specimen, and other CK types were not detected. In 6 primary melanomas, only a few tumor cells were immunopositive for CK 8 and 18, but in 17 cases up to one quarter, and in 2 tumors more than one quarter, of them were labeled. The positive cells were spindle, epithelioid, or intermediate in shape, and tended to be more frequent in mixed than in spindle cell melanomas. MAbs CAM 5.2 and CY-90 did not react with any of the 16 liver metastases, but labeled 7 of 15 other metastases. Metastases were somewhat more common when the primary tumor was immunoreactive for CK 8 and 18, apparently because CKs were more frequent in mixed cell melanomas. Although CK expression is of diagnostic significance and can denote low levels of epithelioid differentiation, it is not an independent prognostic factor in malignant uveal melanoma.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Antibodies, Monoclonal; Female; Humans; Immunoenzyme Techniques; Immunohistochemistry; Keratins; Male; Melanoma; Middle Aged; Prognosis; Retrospective Studies; Uveal Neoplasms

To determine whether ocular melanomas are immunophenotypically identical to cutaneous melanomas, 34 primary and metastatic choroidal melanomas representing all major histotypes defined by the Callender's classification, plus one melanoma of the iris and one conjunctival melanoma, were subjected to a panel of immunostains designed to distinguish anaplastic biopsies of cutaneous melanomas from carcinomas and lymphomas. All ocular melanomas were found to express the intermediate filament vimentin but not keratin, and all but 2 were melanotic by immunostaining. Thirty-three of 34 (97%) choroidal melanomas were strongly stained with a rabbit polyclonal antibody (P-S100) developed against the S100 protein family. In contrast, none of 14 spindle cell type primary lesions was stained with a monoclonal antibody (MAB-079) specific for both S100 alpha and S100 beta, the best-characterized S100 polypeptides. Furthermore, only 2 of 5 epithelioid and 3 of 10 mixed-cell-type melanomas were weakly reactive. Overall, 14.7% (5 of 29) were stained. In comparison, MAB079 stained 85% of all cutaneous melanomas. Five metastases of choroidal melanomas (spindle B, epithelioid, and mixed cell types) from different organ sites also were stained by P-S100 but not by MAB079. These findings were corroborated by immunostaining with another monoclonal antibody (MAB4D4) specific for S100 beta. Differential staining by the polyclonal but not the monoclonal antibodies suggests the possible presence of a variant S100 polypeptide(s) in choroidal melanomas. Since S100 alpha, S100 beta, and related proteins appear to be physiologically important, additional studies of these S100 proteins may shed light on the etiology or pathology of choroidal melanomas.

Topics: Antibodies, Monoclonal; Chi-Square Distribution; Conjunctival Neoplasms; Humans; Immunoenzyme Techniques; Iris Neoplasms; Keratins; Melanoma; Phenotype; S100 Proteins; Skin Neoplasms; Uveal Neoplasms; Vimentin

A 51-year-old white man was found to have a deeply pigmented mass in the ciliary body and peripheral choroid of his right eye with an associated vitreous hemorrhage. Although the tumor appeared to be a ciliochoroidal melanoma, a melanocytoma and adenoma of the pigment epithelium also were considered in the differential diagnosis. The tumor was removed by a large partial lamellar sclerocyclochoroidectomy. Results of histopathologic evaluation showed a cystic adenoma of the pigmented ciliary epithelium. To the authors' knowledge, this was the first immunohistopathologic study of this tumor. Results of the study showed marked immunoreactivity for low molecular weight cytokeratins, vimentin, and S-100 protein. These immunohistochemical studies are consistent with the origin of this tumor from pigment epithelial cells.

Topics: Antibodies, Monoclonal; Ciliary Body; Cystadenoma; Epithelium; Fundus Oculi; Humans; Immunohistochemistry; Keratins; Male; Middle Aged; S100 Proteins; Uveal Neoplasms; Vimentin