Functional and Morphologic Analysis of the Fluid-Conducting Meshwork in Xenografted Cutaneous and Primary Uveal Melanoma

PURPOSE. In primary uveal and cutaneous melanoma lesions, extracellular matrix (ECM) is often deposited in arcs, loops, and network patterns. Based on prognostic relevance, these patterns appear to play a significant role in facilitating metastasis. It has been demonstrated that these patterns were capable of transmitting fluid. The current study was undertaken to elucidate further the functional role of these patterns in tumor perfusion and to examine the composition of the patterns by immunohistochemistry. METHODS. To study the role of these patterns in perfusion, fluorochrome-labeled bovine serum albumin, bovine insulin, and dextrans of different molecular sizes were injected intravenously into nude mice bearing subcutaneous human cutaneous melanoma xenografts. Distribution of the human melanoma cells and murine host cells was analyzed by DNA in situ hybridization. To elucidate the composition of these patterns, human uveal melanoma tissues were analyzed for expression of ECM components by immunohistochemistry. RESULTS. Small molecules (Stokes' radius Ͻ4.4 nm) crossed the vessel wall and spread along the ECM patterns within 2 to 10 minutes, whereas larger molecules (Stokes' radius ϳ5.8 nm) required 30 to 45 minutes to enter. Murine host cells were found exclusively in the ECM pattern compartment. In primary uveal melanoma, different types of collagen, ECM-associated heparan sulfate proteoglycans, and different types of cells were present in the patterns. CONCLUSIONS. The data suggest that the ECM deposited as arcs, loops, and network patterns, accommodate the transport of plasma-derived molecules, (e.g., nutrients), to the tumor lesion, thus enhancing tumor growth and progression, and facilitating infiltration of tumor tissue by host-derived cells. (Invest Ophthalmol Vis Sci. 2005;46:3013-3020

Relation of arterial geometry to luminal narrowing and histologic markers for plaque vulnerability: the remodeling paradox

AbstractObjective. To relate local arterial geometry with markers that are thought to be related to plaque rupture.Background. Plaque rupture often occurs at sites with minor luminal stenosis and has retrospectively been characterized by colocalization of inflammatory cells. Recent studies have demonstrated that luminal narrowing is related with the mode of atherosclerotic arterial remodeling.Methods. We obtained 1,521 cross section slices at regular intervals from 50 atherosclerotic femoral arteries. Per artery, the slices with the largest and smallest lumen area, vessel area and plaque area were selected for staining on the presence of macrophages (CD68), T-lymphocytes (CD45RO), smooth muscle cells (alpha-actin) and collagen.Results. Inflammation of the cap or shoulder of the plaque was observed in 33% of all cross sections. Significantly more CD68 and CD45RO positive cells, more atheroma, less collagen and less alpha-actin positive staining was observed in cross sections with the largest plaque area and largest vessel area vs. cross sections with the smallest plaque area and smallest vessel area, respectively. No difference in the number of inflammatory cells was observed between cross sections with the largest and smallest lumen area.Conclusion. Intraindividually, pathohistologic markers previously reported to be related to plaque vulnerability were associated with a larger plaque area and vessel area. In addition, inflammation of the cap and shoulder of the plaque was a common finding in the atherosclerotic femoral artery

EMAP-II expression is associated with macrophage accumulation in primary uveal melanoma.

Contains fulltext : 144480.pdf (publisher's version ) (Open Access)PURPOSE: Primary uveal melanoma may contain arcs, loops, and networks of periodic acid-Schiff (PAS)-positive patterns, along which numerous macrophages are present. Their recruitment into tumor tissue is mediated by chemotactic cytokines, for which vascular endothelial growth factor (VEGF)-C and endothelial monocyte-activating polypeptide ((EMAP)-II are candidates. In this study, the extent of VEGF-C and EMAP-II immunoreaction was related to infiltration of macrophages. METHODS: Serial sections of 25 primary uveal melanoma lesions were analyzed by immunohistochemistry. RESULTS: The analysis showed no correlation of VEGF-C immunoreaction and localization of macrophages. However, accumulation of macrophages occurred at sites of EMAP-II expression, especially in areas containing nests of tumor cells, surrounded by arcs, loops, and network patterns. In tumors with a strong EMAP-II immunoreaction, the adhesion molecule intracellular adhesion molecule (ICAM)-1 was strongly expressed on endothelial cells. EMAP-II-positive endothelial cells did not express VEGF receptor-2. However, extensive release of von Willebrand factor was observed. Signs of apoptosis were found neither in tumor cells nor endothelial cells. CONCLUSIONS: In uveal melanoma, macrophages accumulate at sites of EMAP-II expression. Based on the results, it may be hypothesized that this process of chemotaxis is facilitated by EMAP-II-dependent expression of ICAM-1 on vascular endothelial cells and concomitantly leads to localized vascular damage, as indicated by release of von Willebrand factor

Access to evidence-based treatment among Muslim females with obsessive-compulsive disorder washing subtype: influence of religious affiliation and scrupulosity

This thesis presents the findings from three studies conducted to investigate the relationship between religiosity and Obsessive Compulsive Disorder symptom presentation in Muslim females, their help seeking pathways regarding religious OCD symptoms, and the beliefs, attitudes, experiences and behaviour of Imams regarding scrupulosity. Study 1 examined religiosity and OCD symptom manifestation in a sample of 139 high and low religious Muslim women with or without OCD washing subtype (OCD-W) in Iran. High religious Muslims with OCD-W reported being diagnosed with OCD at a later age, reported more severe OCD symptom severity at the time of diagnosis, and scored higher on self-report measures of OCD symptomatology compared to low religious Muslims with OCD-W. Study 2 employed qualitative interviews to investigate the impact of religion on OCD symptoms and the treatment-seeking experience in five Muslim women with OCD-W living in Australia. Excessive religious washing and repeating rituals before prayer were the most common compulsions reported by participants. Participants performed these rituals to prevent being punished by God and firstly sought help for OCD from Imams, not mental health professionals. There was an average of eight years between the age at which OCD onset and diagnosis of OCD by a mental health professional. Using an online survey completed by 64 Sunni and Shia Imams from Australia and Iran, Study 3 examined their attitudes, beliefs and experiences particularly concerning scrupulosity and OCD treatment. Findings revealed that the majority of Imams were unfamiliar with scrupulosity as a mental problem. Additionally, Sunni Imams were more likely to recommend suggestions inconsistent with the Exposure and Response Prevention treatment approach when asked for advice by congregation members about dealing with religious obsessions or compulsions. Research implications and limitations are discussed

Lack of lymphangiogenesis despite coexpression of VEGF-C and its receptor Flt-4 in uveal melanoma.

Item does not contain fulltextPURPOSE: Because lymphatic vessels are absent from the normal eye and because uveal melanomas are presumed to spread by a hematogenous route in the absence of tumor exposure to conjunctival lymphatics, this study was undertaken to investigate the presence of lymphatic vessels in primary uveal melanomas. METHODS: The presence of lymphatics in 2 control eyes and in 33 primary uveal, 10 primary cutaneous, and 3 metastatic cutaneous melanomas was evaluated by using a double-immunostaining protocol that differentially highlights blood and lymphatic vasculature. In addition, 14 uveal melanomas were immunostained for the lymphatic growth factor vascular endothelial growth factor (VEGF)-C (with anti-VEGF-C polyclonal antibodies [pAbs]), its receptors Flt-4 (with monoclonal antibody [mAb] 9D9) and KDR (with anti-KDR mAb [Clone KDR-2]), and the hemangiogenic factor VEGF-A (with anti-VEGF pAbs). RESULTS: Lymphatics were not detected in normal eyes or in uveal melanoma. As a consequence, signs of lymphangiogenesis were not present. There was coexpression of VEGF-C with Flt-4 and KDR in 6 (43%) of the 14 melanomas. Staining for VEGF-A was completely negative in 25 uveal melanomas analyzed. CONCLUSIONS: The strictly hematogenous metastasis of primary uveal melanomas is explained by the absence of lymphatics in and around the tumor. The current data suggest that, in the presence of endothelial Flt-4, VEGF-C expression is not sufficient to induce lymphangiogenesis from preexisting blood vessels in human cancer

Presence of a fluid-conducting meshwork in xenografted cutaneous and primary human uveal melanoma.

Item does not contain fulltextPURPOSE: Recently, it was reported that tumor cells themselves generate channels and networks in three-dimensional culture and can be found lining channels (some containing red blood cells [RBCs]) in vivo, and they express endothelial or vascular genes in aggressive uveal melanoma. The implications of these data for current insights in the involvement of angiogenesis in tumor growth, metastasis and therapeutic intervention are considerable. Therefore, this possibility was investigated in the current study. METHODS: Thirty human uveal melanomas and 20 xenografts of human cutaneous melanoma were analyzed by Azan histochemistry and immunostaining of endothelial markers. Additionally, in xenografted tumors a tracer study was performed with confocal microscopy and immunoelectron microscopy. RESULTS: Lumina or spaces without endothelial lining containing RBCs were not detected in any lesion. Functional evaluation of the vasculature in xenografts demonstrated rapid tracer appearance both inside and outside blood vessels. Outside blood vessels it spread along matrix networks of arcs and back-to-back loops. Confocal microscopy showed that this extracellular matrix was deposited as stromal sheets around nests of tumor cells. Laminin immunostaining revealed that between sheets surrounding adjacent nests, spaces were present. These spaces were filled, however, with collagen and different types of cells, including cells stained for macrophage markers. CONCLUSIONS: Although no evident endothelium-free and RBC-containing channels were present in the tissues examined, there are fluid-conducting spaces in the form of stromal sheets between nests of tumor cells. In this stromal network, blood vessels are embedded. The authors postulate that this extracellular matrix tissue represents a fluid-conducting meshwork

Functional and morphologic analysis of the fluid-conducting meshwork in xenografted cutaneous and primary uveal melanoma.

Contains fulltext : 47821.pdf (publisher's version ) (Closed access)PURPOSE: In primary uveal and cutaneous melanoma lesions, extracellular matrix (ECM) is often deposited in arcs, loops, and network patterns. Based on prognostic relevance, these patterns appear to play a significant role in facilitating metastasis. It has been demonstrated that these patterns were capable of transmitting fluid. The current study was undertaken to elucidate further the functional role of these patterns in tumor perfusion and to examine the composition of the patterns by immunohistochemistry. METHODS: To study the role of these patterns in perfusion, fluorochrome-labeled bovine serum albumin, bovine insulin, and dextrans of different molecular sizes were injected intravenously into nude mice bearing subcutaneous human cutaneous melanoma xenografts. Distribution of the human melanoma cells and murine host cells was analyzed by DNA in situ hybridization. To elucidate the composition of these patterns, human uveal melanoma tissues were analyzed for expression of ECM components by immunohistochemistry. RESULTS: Small molecules (Stokes' radius <4.4 nm) crossed the vessel wall and spread along the ECM patterns within 2 to 10 minutes, whereas larger molecules (Stokes' radius approximately 5.8 nm) required 30 to 45 minutes to enter. Murine host cells were found exclusively in the ECM pattern compartment. In primary uveal melanoma, different types of collagen, ECM-associated heparan sulfate proteoglycans, and different types of cells were present in the patterns. CONCLUSIONS: The data suggest that the ECM deposited as arcs, loops, and network patterns, accommodate the transport of plasma-derived molecules, (e.g., nutrients), to the tumor lesion, thus enhancing tumor growth and progression, and facilitating infiltration of tumor tissue by host-derived cells

Induction of vascular endothelial growth factor receptor-3 expression on tumor microvasculature as a new progression marker in human cutaneous melanoma.

Item does not contain fulltextThe anatomical relation between a malignant tumor and its vascular and lymphatic bed is an important factor influencing metastasis. Lack of specific markers for the lymphatic endothelium has long hampered a reliable detection of lymphatics. Here, we demonstrate that lymphatic endothelium can reliably be identified in a panel of different normal tissues and of benign and malignant tumors. Application of the previously described PAL-E/CD31 double staining protocol differentiates between blood capillaries and veins on one hand and lymphatic vessels on the other. Blood vessel marker CD34, absent from lymphatics, was used additionally to classify arteries. We found that the lymphatic vascular endothelial growth factor receptor-3 (VEGFR-3, also known as Flt-4) was present on both lymphatic and blood vessels in 76 of 113 malignant tumors [adenocarcinoma of kidney (n = 3), colon (n = 3) and liver (n = 3), breast (n = 9) and squamous cell carcinoma (n = 5), primary (n = 81), and metastatic (n = 9) melanoma]. No evident signs of tumor-induced lymphangiogenesis were observed. Evaluation of a series of 110 melanocytic skin lesions indicated that VEGFR-3 expression is confined to the lymphatic vasculature in benign lesions. However, its expression emerges on the blood neovasculature in malignant lesions as soon as metastatic potential develops. We conclude that induction of VEGFR-3 expression on tumor blood vessels may be a general phenomenon that would make VEGFR-3 a marker for tumor endothelium. In addition, we propose VEGFR-3 expression as a new microvascular progression marker in cutaneous melanoma

Induction of vascular endothelial growth factor receptor-3 expression on tumor microvasculature as a new progression marker in human cutaneous melanoma.

The anatomical relation between a malignant tumor and its vascular and lymphatic bed is an important factor influencing metastasis. Lack of specific markers for the lymphatic endothelium has long hampered a reliable detection of lymphatics. Here, we demonstrate that lymphatic endothelium can reliably be identified in a panel of different normal tissues and of benign and malignant tumors. Application of the previously described PAL-E/CD31 double staining protocol differentiates between blood capillaries and veins on one hand and lymphatic vessels on the other. Blood vessel marker CD34, absent from lymphatics, was used additionally to classify arteries. We found that the lymphatic vascular endothelial growth factor receptor-3 (VEGFR-3, also known as Flt-4) was present on both lymphatic and blood vessels in 76 of 113 malignant tumors [adenocarcinoma of kidney (n = 3), colon (n = 3) and liver (n = 3), breast (n = 9) and squamous cell carcinoma (n = 5), primary (n = 81), and metastatic (n = 9) melanoma]. No evident signs of tumor-induced lymphangiogenesis were observed. Evaluation of a series of 110 melanocytic skin lesions indicated that VEGFR-3 expression is confined to the lymphatic vasculature in benign lesions. However, its expression emerges on the blood neovasculature in malignant lesions as soon as metastatic potential develops. We conclude that induction of VEGFR-3 expression on tumor blood vessels may be a general phenomenon that would make VEGFR-3 a marker for tumor endothelium. In addition, we propose VEGFR-3 expression as a new microvascular progression marker in cutaneous melanoma