Lynn M. Gruman

The Prognostic Value of Tumor Blood Vessel Morphology in Primary Uveal Melanoma

BACKGROUND It is possible to identify at least nine vascular patterns in melanomas of the ciliary body and choroid from histologic sections. An association between the presence of at least one closed vascular loop and death from metastases was shown in a matched-pair, case-control study of 40 patients whose eyes were removed for ciliary body or choroidal melanomas. METHODS Two independent observers who were masked to the follow-up of patients examined histologic preparations of 234 eyes removed for ciliary body or choroidal melanomas for the presence of each of the tumor vascular patterns. Statistical analyses included tests for interobserver reliability, Kaplan-Meier survival curves, and the fitting of Cox regression models. RESULTS The detection of each of the nine vascular patterns is highly reproducible. The Cox model indicates that the presence of vascular networks, defined as at least three back-to-back closed vascular loops, is the feature most strongly associated with death from metastatic melanoma. Other significant factors in the Cox model include (in descending order of importance) largest tumor dimension, mitoses, the parallel with cross-linking vascular pattern, age, the presence of tumor-infiltrating lymphocytes, and male gender. CONCLUSIONS The presence of vascular networks provides the most significant association with death from metastatic melanoma of all variables tested. The presence of this pattern should be recorded on pathology reports. If it becomes possible to detect this vascular pattern clinically using a noninvasive imaging technique, then ophthalmologists may be able to determine the likely biologic behavior of a melanoma before resorting to the removal of tissue.

The morphologic characteristics of tumor blood vessels as a marker of tumor progression in primary human uveal melanoma: A matched case-control study☆

Nine morphologic patterns of tumor vessels were identified in eyes removed for ciliary body or choroidal melanoma by the examination of tissue sections stained with fluorescein-conjugated Ulex europaeus I using laser scanning confocal microscopy. This technique also highlights intravascular tumor invasion. Each of these nine morphologic patterns of tumor vessels also may be demonstrated by a modification of the periodic acid-Schiff reaction, viewed with a green narrow band pass filter, but this modified histochemical technique does not accurately identify intravascular tumor invasion. Most tumors have a heterogeneous distribution of vascular patterns. Melanomas in two groups of 20 tumors each were matched by tumor size and location (one group of tumors from patients who survived at least 15 years free of metastatic melanoma after enucleation and one group of tumors from patients who died of metastatic melanoma). A matched case-control analysis indicates that the presence of at least one closed vascular loop in a uveal melanoma is the most significant vascular pattern associated with death from metastatic melanoma after enucleation. Closed loops are associated with other histologic features that are predictive of an unfavorable outcome after enucleation: epithelioid cells and mitotic figures. In this preliminary study the formation of closed vascular loops is a marker of tumor progression in ciliary body and choroidal melanomas.

Biological significance of focal adhesion kinase in ovarian cancer: Role in migration and invasion

Focal adhesion kinase (FAK) is a nonreceptor tyrosine kinase that is activated by integrin clustering. There are limited data regarding the functional role of FAK in ovarian cancer migration and invasion. In the current study, FAK expression was evaluated in ovarian cell lines (nontransformed and cancer), 12 benign ovarian samples, and in 79 invasive epithelial ovarian cancers. All three ovarian cancer cell lines overexpressed FAK compared to the nontransformed cells. The dominant-negative construct called FAK-related nonkinase (FRNK) was introduced into two ovarian cancer cell lines (SKOV3 and 222). FRNK promoted FAK dephosphorylation without changing total FAK levels in these cell lines. Furthermore, FRNK decreased the in vitro invasive ability of ovarian cancer cells by 56 to 85% and decreased migration by 52 to 68%. FRNK-transfected cells also displayed poor cell spreading. Immunohistochemical analysis revealed that the surface epithelium from all benign ovarian samples had weak FAK expression. In contrast, 68% of invasive ovarian cancers overexpressed FAK. FAK overexpression was significantly associated with high tumor stage, high tumor grade, positive lymph nodes and presence of distant metastasis (all P values <0.05). FAK overexpression was also associated with shorter overall survival (P = 0.008). Multivariate analysis revealed that FAK overexpression and residual disease >1 cm were independent predictors of poor survival. These data indicate that FAK is overexpressed in most invasive ovarian cancers and plays a functionally significant role in ovarian cancer migration and invasion. Thus, FAK may be an important therapeutic target in ovarian carcinoma.

The Clinical Relevance of Stromal Matrix Metalloproteinase Expression in Ovarian Cancer

Purpose: Matrix metalloproteinases (MMP) are proteolytic enzymes implicated in cancer progression and metastasis. We sought to determine the role of epithelial (tumor cell–derived) and stromal (host-derived) expression of MMPs in predicting the clinical outcome of patients with epithelial ovarian cancer (EOC). Experimental Design: MMP-2, MMP-9, and membrane type 1 (MT1)-MMP expression was evaluated using immunohistochemistry in 90 invasive EOCs, and samples were scored for epithelial and stromal staining. Results were correlated with clinicopathologic characteristics using univariate and multivariate analyses. Results: High expression of MMP-2, MMP-9, and MT1-MMP in tumor epithelium was detected in 54%, 97%, and 100% of cases, and in stromal compartments, in 38%, 70%, and 38% of cases, respectively. High stromal expression of MMP-2, MMP-9, and MT1-MMP was significantly associated with aggressive features such as high stage, high grade ascites, and positive lymph node status. Kaplan-Meier analysis showed that high epithelial and stromal expression of MMP-2, MMP-9, and MT1-MMP were each significantly associated with shorter disease-specific survival (DSS; P < 0.01). On tree-structured survival analysis, patients with strong epithelial MT1-MMP expression had the shortest DSS, whereas patients with moderate epithelial MT1-MMP and low stromal MMP-9 expression had the longest DSS (P < 0.01). On multivariate analysis, high stromal expression of MMP-9 (P = 0.01) and MT1-MMP (P = 0.04), strong epithelial MT1-MMP (P = 0.01) and high stage (P = 0.04) were independent predictors of poor DSS. Conclusions: Overexpression of stromal MMP-9 and MT1-MMP is independently associated with shorter DSS in EOC. Thus, host-derived MMPs are valuable predictors of clinical outcome in EOC.

Expression of multiple molecular phenotypes by aggressive melanoma tumor cells : role in vasculogenic mimicry

Cutaneous melanoma has been increasing at an alarming rate over the past two decades, however, there are no acceptable histopathological markers that classify various stages of melanoma progression. Recently, the molecular analysis of cancer has contributed significantly to our understanding of the cellular and molecular underpinnings of tumor progression. The data summarized in this review describe the molecular signature of aggressive cutaneous melanoma cells as that of multiple phenotypes which may be similar to a pluripotent, embryonic-like phenotype. An example of the plasticity of this phenotype is demonstrated by the ability of aggressive melanoma cells to engage in vasculogenic mimicry and neovascularization. A review of the current data demonstrating important cellular and molecular determinants of human melanoma vasculogenic mimicry is presented. These findings should stimulate additional studies to address the biological relevance of the multiple molecular phenotypes expressed by aggressive melanoma cells which may lead to the development of new diagnostic markers and therapeutic targets for clinical intervention.

The clinical significance of tumor cell-lined vasculature in ovarian carcinoma: implications for anti-vasculogenic therapy.

Vasculogenic mimicry reflects the plasticity of aggressive tumor cells that express vascular cell markers and line tumor vasculature; such has been demonstrated in aggressive ovarian carcinoma. This study measured the clinical significance of tumor cell-lined vasculature in ovarian carcinomas (n = 77), which was detected in 23 (29.8%) tumors. The data show that tumor cell-lined vasculature was associated with aggressive tumor features and with shorter overall survival (p < 0.001). Cox proportional hazards model revealed that tumor cell-lined vasculature (p = 0.002) was independently associated with poor survival. This is the first study demonstrating the clinical implications of tumor cell-lined vasculature in ovarian carcinoma.

Elevated focal adhesion kinase expression facilitates oral tumor cell invasion

Understanding the molecular mechanisms of metastasis is critical with respect to oral tumorigenesis. The focal adhesion kinase (FAK) is an intracellular tyrosine kinase associated with the regulation of cell growth, migration, and survival. The purpose of the current study was to determine whether elevated FAK expression in oral malignancies was associated with increased invasiveness and oral carcinoma.

Regulating the tumor suppressor gene maspin in breast cancer cells: a potential mechanism for the anticancer properties of tamoxifen.

Purpose: Mammary epithelial cells and the majority of breast cancer tumors require estrogen for continued growth. Antiestrogen therapy alone, or in combination with other drugs, has long been a common procedure for breast cancer treatment and prophylaxis. Thus, there is a critical need to elucidate the mechanism(s) of action of antiestrogen treatment, especially for patients who are at risk of breast cancer development or who are currently receiving hormone therapy. In this study, we examined the ability of hormones to regulate the expression of a tumor suppressor gene, maspin, which is a serine protease inhibitor (serpin) that plays an important role in mammary gland development and is silenced during breast cancer progression. Specifically, our hypothesis tested the clinical efficacy of tamoxifen to regulate maspin expression. Experimental Design: We used maspin promoter luciferase reporter plasmids that were transfected into normal human mammary epithelial (HMEC1331) and MCF-7 breast cancer cells, followed by determination of the effect of hormones and their antagonists on maspin promoter activity. At the protein level, cytosolic fractions from both cell types before and after hormone treatment were subjected to Western blot analysis to determine maspin level. Results and Conclusions: Our studies revealed that the antiestrogen tamoxifen induces maspin promoter activity. Interestingly, antiandrogen flutamide could also induce maspin in both cell lines tested. These observations were further confirmed in patient tissues. These novel findings provide a new mechanism of action for tamoxifen under normal and pathological conditions. More significantly, these findings could have a potential impact on future therapeutic intervention strategies for breast cancer.

The Stem Cell Plasticity of Aggressive Melanoma Tumor Cells

Microarray analysis of melanoma cell lines suggests that aggressive melanomas have a pluripotent, embryonic-like phenotype, implying the possibility of a stem cell origin for tumor components. Aggressive melanoma cells also form vascular structures and express endothelial-associated genes (including vascular endothelial-cadherin and EphA2) critical for vessel formation, indicating that the tumor cells have the plasticity to generate progeny, which express multiple cellular phenotypes with additional biological potential. This does not occur in poorly aggressive tumors, and, thus, expression of these genes is a predictor of biological behavior of the tumor. The aggressive tumor cells were able to participate in the neovascularization of ischemic tissue and produce factors that influence poorly aggressive tumor cells to assume a vascular phenotype. Understanding the molecular underpinnings of the plasticity of melanoma cells may lead to more effective diagnosis, treatment, and prevention measures for aggressive melanoma tumors.