Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027627 (metastases)
 103,950 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

PA2.26 antigen is a small mucin-type transmembrane glycoprotein induced in mouse epidermal keratinocytes during carcinogenesis. It is located at plasma membrane projections, such as microvilli and ruffles, where it interacts with the actin cytoskeleton. Previous studies revealed that ectopic expression of PA2.26 in epidermal MCA3D keratinocytes induces cell surface extensions and increased motility. Here, we show that PA2.26-expressing MCA3D (3D2.26) cell transfectants undergo a phenotypic conversion linked to the acquisition of malignant characteristics. The 3D2.26 cells down-regulate basal keratin K14 and up-regulate vimentin and keratin K8 expression. Immunofluorescence analysis in 3D2.26 cell cultures showed loss of cortical actin filaments and destabilization of adherens junctions mediated by E- and P-cadherin, although both cadherin mRNAs were expressed in the transfectants. When the cadherin protein levels were analyzed in Western blots, no P-cadherin protein or smaller polypeptide E-cadherin forms were detected, suggesting that E- and P-cadherin synthesized in 3D2.26 cells was unstable and proteolytically degraded. Transplantation of 3D2.26 cells into athymic nude mice induced tumors, whereas MCA3D cells and control (3DN) transfectants were not tumorigenic after 72 days postinjection. The phenotype of the tumors was undifferentiated, with mixed regions exhibiting a glandular differentiation pattern in which the presence of numerous surface microvilli was observed at the ultrastructural level. Interestingly, PA2.26 antigen was highly expressed in these microvillous cell surfaces. Tumor cells were vimentin- and K8-positive and showed an aberrant pattern of E-cadherin protein expression in which large cytoplasmic aggregates were found close to the nucleus. Infiltration of tumor cells into lymphatic vessels and the presence of frequent regional lymph node metastases were also observed in the tumors. These results indicate that expression of PA2.26 antigen in premalignant keratinocytes induces a fully transformed and metastatic phenotype, and they suggest an involvement of PA2.26 in malignant progression.
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PMID:Ectopic expression of PA2.26 antigen in epidermal keratinocytes leads to destabilization of adherens junctions and malignant progression. 1109 35

Metastasis to local lymph nodes via the lymphatic vessels is a common step in the spread of solid tumors. To investigate the molecular mechanisms underlying the spread of cancer by the lymphatics, we examined the ability of vascular endothelial growth factor (VEGF)-D, a ligand for the lymphatic growth factor receptor VEGFR-3/Flt-4, to induce formation of lymphatics in a mouse tumor model. Staining with markers specific for lymphatic endothelium demonstrated that VEGF-D induced the formation of lymphatics within tumors. Moreover, expression of VEGF-D in tumor cells led to spread of the tumor to lymph nodes, whereas expression of VEGF, an angiogenic growth factor which activates VEGFR-2 but not VEGFR-3, did not. VEGF-D also promoted tumor angiogenesis and growth. Lymphatic spread induced by VEGF-D could be blocked with an antibody specific for VEGF-D. This study demonstrates that lymphatics can be established in solid tumors and implicates VEGF family members in determining the route of metastatic spread.
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PMID:VEGF-D promotes the metastatic spread of tumor cells via the lymphatics. 1117 37

Metastasis of breast cancer occurs primarily through the lymphatic system, and the extent of lymph node involvement is a key prognostic factor for the disease. Whereas the significance of angiogenesis for tumor progression has been well documented, the ability of tumor cells to induce the growth of lymphatic vessels (lymphangiogenesis) and the presence of intratumoral lymphatic vessels have been controversial. Using a novel marker for lymphatic endothelium, LYVE-1, we demonstrate here the occurrence of intratumoral lymphangiogenesis within human breast cancers after orthotopic transplantation onto nude mice. Vascular endothelial growth factor (VEGF)-C overexpression in breast cancer cells potently increased intratumoral lymphangiogenesis, resulting in significantly enhanced metastasis to regional lymph nodes and to lungs. The degree of tumor lymphangiogenesis was highly correlated with the extent of lymph node and lung metastases. These results establish the occurrence and biological significance of intratumoral lymphangiogenesis in breast cancer and identify VEGF-C as a molecular link between tumor lymphangiogenesis and metastasis.
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PMID:Induction of tumor lymphangiogenesis by VEGF-C promotes breast cancer metastasis. 1117 37

Knowledge of the anatomy and physiology of the lymphatic system is helpful when considering a particular sentinel node biopsy technique. The delicate balance between internal and external pressures in a lymphatic channel can be influenced by the injection volume and by massage in a negative or positive way. The narrow openings in the interendothelial junctions determine the speed of clearance of particles with a certain size, and this has implications for the timing of lymphoscintigraphy and surgery. Tracer uptake and lymph flow are highly variable and depend on a number of factors, some of which are beyond our control. The lymphatic anatomy is not completely understood despite numerous studies since the end of the 18th century. Several topics have been elucidated in more recent studies and through experience with sentinel node biopsy. First, although axillary drainage is the principal lymphatic path of the breast, any drainage pattern from any quadrant of the breast can occur. Second, most lymph from the breast flows to the nodal basins with a direct course, not passing through the subareolar plexus. Another relevant point is that gentle massage encourages lymph flow and facilitates sentinel node detection. What problems do we still face in clinical practice? The optimum size and number of labeled colloid particles remain to be established. The optimum volume of the tracer also remains to be determined. But the main controversy concerns the injection site. Although the intradermal injection technique has attractive practical features, there is currently insufficient certainty that drainage of tracer injected anywhere in or underneath the skin of the breast reflects drainage from the cancer. Connections between collecting lymphatic vessels from the tumor site and the collecting vessels from the skin and subdermal lymphatics can explain the concordance between intraparenchymal and superficial injections in most patients. To determine the technique that yields the best sentinel node identification rate with the lowest possible false-negative rate would require a large randomized trial with all patients undergoing a complete lymph node dissection and evaluation of all other axillary lymph nodes with serial sections and immunohistochemistry. Current knowledge about sensitivity is based on examination of the other axillary nodes with hematoxylin and eosin staining and not with immunohistochemistry, with the exception of two studies. (33,76) In addition, a complete level I to III dissection may not have been done in all patients, and it is not certain that pathologists removed and examined all the nodes from the specimens. The proposed study seems impossible now that routine axillary node dissection has been abandoned by the larger centers around the world. Choosing the most attractive approach requires determining the aim of lymphatic mapping. A superficial injection technique may be adequate when the purpose is to spare patients without lymph node metastases in the axilla an unnecessary axillary node dissection. An intraparenchymal injection technique should be used when the additional purpose is to determine the stage as accurately as possible and to identify sentinel nodes elsewhere.
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PMID:Anatomy and physiology of lymphatic drainage of the breast from the perspective of sentinel node biopsy. 1158 78

The first case of primary cutaneous squamous cell carcinoma (SCC) to cause zosteriform and epidermotropic metastasis to skin is reported. The patient is a 72-year-old Japanese woman. A cutaneous SCC appeared on the lateral side of her right knee and was removed. After dissection of the right inguinal lymph nodes, which revealed metastases, and irradiation of the right inguinal region, the patient presented with slightly pruritic and painful erythematous papules on the right hip and small brownish papules and vesicles with crusts on the anterior side of the right thigh. The eruptions were in a zosteriform distribution along the right L1 to L3 dermatomes. Histologically neoplastic squamous cell nests were observed in the epidermis, below the epidermal-dermal junction, and within lymphatic vessels in the deeper reticular dermis. We postulate that neoplastic cells with the ability to fuse with adjacent squamous epithelium may have been carried beneath the basal lamina or to the epidermis via dermal lymphatic backflow, resulting in epidermotropic metastasis.
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PMID:Zosteriform and epidermotropic metastatic primary cutaneous squamous cell carcinoma. 1139 Nov 2

Synchronous multifocal/multicentric osteosarcoma (MOS) is a rare variant of osteosarcoma. We report here an autopsy case of a 15-year-old boy with MOS. Radiological examinations showed multiple sclerotic lesions in the left distal femur and in the ipsilateral proximal tibia without pulmonary metastasis at the first examination. Histological examination showed osteoblastic-type osteosarcoma. Despite high-dose chemotherapy the patient died of multiple bone and lung involvements 6 months after the initial diagnosis. Autopsy examination revealed prominent invasion of the tumor cells into lymphatic vessels and pleural dissemination without the formation of bulky, nodular metastasis in the lungs. Metastases in pulmonary hilar lymph nodes were noted without metastasis in other organs. Immunohistochemistry revealed that p53 protein was positive in most of the tumor cells. In summary, the present case was characterized by multiple bone involvement and prominent lymphatic spread of sarcoma cells in the lungs.
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PMID:Synchronous multifocal osteosarcoma with lymphatic spread in the lung: an autopsy case report. 1177 66

Extraocular sebaceous carcinoma is an uncommon neoplasm usually localized on the head and neck. We report a case of sebaceous carcinoma of the axillary skin with a highly aggressive behavior. The patient was a 43-year-old black man who developed multiple cutaneous and lymph node metastases shortly after the excision of primary sebaceous carcinoma of the axillary skin. Many neoplastic aggregations were identified within the lumina of the dermal lymphatic vessels in the excised specimen of the primary neoplasm. Although extraocular sebaceous carcinoma has been traditionally considered a less aggressive neoplasm than its ocular counterpart, a review of the literature and this case demonstrate that extraocular sebaceous carcinoma may also lead to disseminated metastatic disease.
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PMID:Highly aggressive extraocular sebaceous carcinoma. 1180 79

The capacity of malignant tumours to metastasize to distant tissues presents a huge problem for the treatment of cancers using conventional surgical and cytotoxic drug therapies. One of the main routes for tumour spread is via the lymphatic vessels, an important conduit for tumours such as breast, lung and gastrointestinal tract that frequently colonize regional lymph nodes. In comparison with the vasculature however, little is known about the biology of tumour lymphatics, tumour lymphangiogenesis or the mechanisms that regulate entry and subsequent migration of tumour cells within lymphatic vessels. This situation has persisted because of the lack of specific molecular markers with which to visualize even normal lymphatics within tissues or to isolate lymphatic endothelial cells for in vitro experimental analysis. Just recently however, novel markers for lymphatic endothelial cells have been identified and their availability has revolutionized research in this field. In this article we highlight the main characteristics of these markers and review recent progress in their use to study tumour lymphangiogenesis.
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PMID:New molecular markers for the study of tumour lymphangiogenesis. 1190 82

The angiogenic factor vascular endothelial growth factor-D (VEGF-D) isa ligand for VEGF receptor-3 (VEGFR-3/Flt-4) and receptor-2 (VEGFR-2/KDR)and is implicated in the development of lymphatic vessels and promotion of lymphatic metastases. We assessed the expression of VEGF-D and VEGFR-3 in relation to microvessel density (MVD) in colorectal carcinomas (CRC), adenomas, and adjacent normal tissue by immunohistochemistry on consecutive archival sections. VEGF-D was detected in malignant and benign epithelium and in some smooth muscle of the colorectum. High-grade VEGF-D expression was observed frequently (74%) in CRC compared with adenomas (0%) and adjacent normal mucosa (22%). High-grade VEGF-D expression was not correlated with MVD, Dukes' stage (A to C), or tumor differentiation, but was associated with lymphatic involvement and patient survival. By multivariate analysis, VEGF-D expression was found to be an independent prognostic factor for both disease-free and overall survival. VEGFR-3 expression was detected in a subset of vessels, typically thin-walled and devoid of RBCs, in 89% of CRC cases examined. VEGFR-3-positive vessel densities increased progressively from normal mucosa to adenomas and carcinomas and were correlated with MVD, but not with Dukes' stage (A to C), tumor differentiation, or VEGF-D expression. VEGFR-3 expression was spatially associated with macrophage-rich inflammatory infiltrates, which were significantly more frequent among VEGFR-3-positive cases. We conclude that VEGF-D expression, but not that of its receptor VEGFR-3, is an independent prognostic indicator in CRC. VEGF-D expression may be associated with disease outcome through the promotion of lymphatic involvement/metastases.
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PMID:Vascular endothelial growth factor-D expression is an independent prognostic marker for survival in colorectal carcinoma. 1191 38

The spread of cancer cells to regional lymph nodes through the lymphatic system is the first step in the dissemination of breast cancer. In several human cancers including those of the breast and prostate, the expression of vascular endothelial growth factor C (VEGF-C) is associated with lymph node metastasis. Our study was undertaken to evaluate the effect of VEGF-C on metastasis of poorly invasive, estrogen dependent human MCF-7 breast cancer cells. MCF-7 breast cancer cells transfected with VEGF-C (MCF-7-VEGF-C) were grown as tumors in the mammary fat pads of nude mice implanted with subcutaneous estrogen pellets. Tumor lymphangiogenesis and lymph node metastasis were studied immunohistochemically using antibodies against lymphatic vessel hyaluronan receptor -1 (LYVE-1), VEGF receptor-3 (VEGFR-3), PECAM-1, pan-cytokeratin and estrogen dependent pS2 protein. Overexpression of VEGF-C in transfected MCF-7 cells stimulated in vivo tumor growth in xenotransplanted mice without affecting estrogen responsiveness. The resulting tumors metastasized to the regional lymph nodes in 75% (in 6 mice out of 8, Experiment I) and in 62% (in 5 mice out of 8, Experiment II) of mice bearing orthotopic tumors formed by MCF-7-VEGF-C cells whereas no metastases were observed in mice bearing tumors of control vector-transfected MCF-7 cells (MCF-7-Mock). The density of intratumoral and peritumoral lymphatic vessels was increased in tumors derived from MCF-7-VEGF-C cells but not MCF-7-Mock cells. Taken together, our results show that VEGF-C overexpression stimulates tumor lymphangiogenesis and induces normally poorly metastatic estrogen-dependent MCF-7 tumors to disseminate to local lymph nodes. These data suggest that VEGF-C has an important role in lymph node metastasis of breast cancer even at its hormone-dependent early stage.
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PMID:VEGF-C induced lymphangiogenesis is associated with lymph node metastasis in orthotopic MCF-7 tumors. 1194 78


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