Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0025202 (melanoma)
 69,561 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We report 6 cases of desmoplastic melanoma. Upon removal and histologic examination, each lesion consisted of a dermal nodule of fascicles of spindle cells, many of which showed pleomorphic and hyperchromatic nuclei. Fascicles, as well as single cells, were seen infiltrating the dermal collagen. Lentiginous hyperplasia of melanocytes with varying but usually slight cellular atypia overlay the dermal proliferations in all cases. Melanophages and some pigmented cells, albeit few in number, were present in the infiltrate, whereas mitotic figures were also noted. These features are most consistent with desmoplastic melanoma, a rare tumor of which a limited number of cases has been described. The clinical and histopathologic features of the lesions presented exemplify the diagnostic and therapeutic dilemma associated with desmoplastic melanoma.
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PMID:Desmoplastic melanoma: clinicopathologic aspects of six cases. 163 68

We previously reported on the altered expression of a third actin in mouse-B16 melanoma associated with malignant progression. While further investigating the relationship of cytoskeletal proteins to malignancy, we found that the expression of vinculin was higher in weakly metastatic B16-F1 cells than in highly metastatic B16-F10 cells. By Northern blot analysis, the mRNA expression of vinculin in B16-F1 was also shown to be higher than in B16-F10. Immunofluorescence staining showed a clear dotted distribution of vinculin in B16-F1, but only a weak and diffuse distribution in B16-F10. The dotted distribution tended to be larger in B16-F1 and when cultured on Matrigel and fibronectin than on laminin and type IV collagen. An alteration in the expression of vinculin was also observed in other cell systems. Vinculin was detected in both normal 3Y1 and in relatively weakly malignant transformed 3Y1 cell lines, while vinculin was either scarcely detected or not detected at all in more malignant cell lines. These results suggest that the suppression of vinculin is closely related to malignant progression in both the B16-melanoma and 3Y1 cell systems.
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PMID:Differential expression of vinculin between weakly and highly metastatic B16-melanoma cell lines. 164 65

Using Ulex europaeus I lectin (UEA1) to demonstrate endothelial cells, we have previously shown that frequency of capillary invasion correlates closely with maximum tumor thickness in primary cutaneous melanoma. UEA1 demonstrates both vascular and lymphatic capillaries; however, only vascular capillaries possess basement membranes. In order to ascertain whether these capillaries were lymphatic or vascular, we employed a double staining technique, using UEA1 in conjunction with a monoclonal anti-type IV collagen antibody. We studied 21 primary cutaneous melanomas. Seven of the 21 included lymphatic capillaries, while 14 did not. These lymphatic capillaries were very sparse and appeared to be residual dermal lymphatics rather than a result of lymphangiogenesis. Lymphatic permeation by melanoma was not seen in any of the tumors studied. There was no apparent association among tumor thickness, level of invasion, growth phase, necrosis, regression or mitotic index, and presence of lymphatics within the melanomas. Although scanty lymphatics are present in some primary cutaneous melanomas, this study does not suggest that lymphatic permeation plays a major role in the spread of melanoma to locoregional lymph nodes.
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PMID:Lymphatics in primary cutaneous melanoma. 169 Sep 53

We studied two cases of pigmented neuroectodermal tumor of infancy (PNTI) by routine light microscopy and immunohistochemistry on formalin fixed, paraffin embedded tissues using antibodies to HMB-45 "melanoma associated" antigen, S-100 protein, neuron specific enolase (NSE), Leu-7 antigen, chromogranin, epithelial membrane antigen, collagen Type IV, alpha-fetoprotein and muscle-specific actin and to the intermediate filaments cytokeratin (CK), vimentin, desmin and neural filaments. We found that the large epithelioid cells, many of which contained melanin pigment, were strongly positive for CK and HMB-45, and less intensively positive for vimentin and NSE. The small neuroblast-like cells revealed only focal, weak NSE positivity. Both cell types were negative for S-100 protein and for the other antigens examined. Our results suggest that: (1) the large and small cell populations in PNTI have different immunophenotypes; (2) the expression of CK and HMB-45, together with the S-100 negativity, appears unique for the pigmented cells; and (3) this profile may be helpful in the exclusion of melanoma and peripheral neuroblastoma from the differential diagnosis.
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PMID:Pigmented neuroectodermal tumor of infancy. A light microscopic and immunohistochemical study. 170 90

We have characterized a number of monoclonal anti-idiotype antibodies (mAb2s) made against a monoclonal antitumor antibody, MEM136. The monoclonal antibody 1 (mAb1) MEM136 recognizes an epitope on human melanoma-associated proteoglycan and blocks melanoma cell interaction with basement membrane components in vitro. The anti-idiotype antibodies (Ab2s) made against MEM136 each cross-inhibited, to varying degrees, their binding to MEM136. Thus, the mAb2s recognized overlapping idiotopes on MEM136. In an attempt to identify potential internal image candidates we set up a cell migration inhibition assay. In this assay, migration of melanoma-associated proteoglycan-positive Colo38 cells was determined through a membrane barrier impregnated with Matrigel, which is composed of extracellular matrix components, i.e., collagen type IV, heparan sulfate, and laminin. Interestingly, only Ab2s IM06 and IM32 inhibited melanoma cell migration. Additional studies indicate that of eight mAb2s tested, only IM32 and IM06 induced anti-MPG responses in rabbits. The possibility that IM32 and IM06 bear images of melanoma cell surface-associated proteoglycan epitopes is discussed.
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PMID:Monoclonal anti-idiotypic antibodies to human melanoma-associated proteoglycan antigen: generation and characterization of anti-idiotype antibodies. 171 Jan 68

Phorbol esters which activate protein kinase C (PKC) have been shown to enhance experimental lung metastasis. Therefore, it was reasoned that inhibitors of PKC might also modulate metastasis. We have investigated this possibility using a PKC inhibitor, MDL 27,032 [4-propyl-5(4-pyridinyl)-2(3H)-oxazolone], as well as staurosporine and H-7. Treatment of B16F1 murine melanoma cells with MDL 27,032 for 24 h in culture and subsequent i.v. injection of the cells into mice resulted in greater than 90% inhibition of lung metastasis. Inhibition of metastasis was time dependent, with 90% of maximum inhibition occurring by 8 h of incubation. The 50% inhibitory concentration (IC50) for inhibition of metastasis with MDL 27,032 was 7 microM, a value similar to that for the inhibition of B16F1 membrane-associated PKC (IC50 = 13 microM) but not cytosolic PKC (IC50 = 54 microM). B16F1 cells treated with MDL 27,032 for 24 h were less adherent than untreated cells to extracellular matrix/basement membrane proteins. Adhesion to fibrinogen and collagen IV was inhibited (IC50 = 6 microM and 48 microM, respectively) by MDL 27,032, whereas adherence to laminin and fibronectin was not affected, indicating that the drug affects specific adhesion molecules. MDL 27,032-treated cells were also found to be less adherent than untreated cells to human umbilical vein endothelial cells. The phosphorylation of an 80-kDa B16F1 cell plasma membrane protein was stimulated under conditions known to stimulate PKC activity, and MDL 27,032 inhibited this phosphorylation in a dose-dependent manner. MDL 27,032 was more potent than H-7 for the inhibition of metastasis but was significantly less potent than staurosporine. These results support the hypothesis that there is a critical role for PKC-mediated phosphorylation of cell surface adhesion receptors in metastasis.
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PMID:Inhibition of experimental metastasis and cell adhesion of B16F1 melanoma cells by inhibitors of protein kinase C. 173 79

Antigen expression was studied by immunohistochemistry in 133 human melanocytic skin lesions to gain insight into the initial steps of tumor development, i.e. in particular the change from melanocytes to benign nevi. We refer to the proposed progression model of Clark and co-workers. The following types of antigens were investigated: (i) intermediate filament antigens (vimentin), (ii) melanoma-associated antigens (HMB-45, NKI/C3, MA-930, LS59), (iii) proliferation-associated antigens (S-100, Ki67, Ro/SSA, calmodulin), (iv) progression-associated antigens (HLA-DR, ICAM-1), and (v) basal membrane antigens (bullous pemphigoid antigen, laminin, fibronectin, collagen type IV). The intensity of expression and the topography of immunoreactive pigment cells were compared with the stage of tumor progression. Special attention was paid to the early steps of this process, i.e. the disturbance of the epidermal melanin unit and the development of melanocytic ("nevocellular")nevi. A dramatic shift of antigen expression (antigen types [i] to [v]) was noted in benign nevi compared with melanocytes. Nevi with cellular atypia disclosed a tendency towards an increased percentage of tumor cells reactive for melanoma- and progression-related antigens (types [ii] and [iv]). However, there was no clear cut level of distinction of antigen expression (types [i] to [v]) between benign and primary malignant melanocytic tumors. So-called dysplastic nevi resembled benign tumors or melanocytes rather than malignant melanoma. Metastatic melanoma of skin showed a relatively high number of Ki67-positive, cycling melanoma cells. The results have a bearing on the concepts of melanocytic nevus ontogenesis and "maturation". It appears that melanocytes lose maturity on their way down to the dermis in contrast to traditional concepts (Abtropfung); this might be of importance for our understanding of melanoma development in association with melanocytic nevi. Our findings are discussed with regard to Clark's model of tumor progression.
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PMID:The initial steps of tumor progression in melanocytic lineage: a histochemical approach. 174 97

Human umbilical vein endothelial cells grew well in dishes coated with collagen types I, II, III, or IV. However, the same cells tended to detach themselves from dishes coated with type V collagen, and cell proliferation in these dishes was inhibited. Such anti-adhesive activity was partially retained by heat-denatured type V collagen or by its alpha 1 chain, but not by its alpha 2 chain. Several other cell types did not adhere to the type V collagen substratum even in the presence of 10% serum. The cell types strongly inhibited from adhering by type V collagen included Swiss mouse 3T3 cells and their MSV-transformants, BALB/c 3T3 cells and their methylcholanthrene-transformants, NIH 3T3 cells and their ras-transformants, BHK cells, CHO-9 cells, CHO-K1 cells, and mouse melanoma B16-F10 cells. Using Swiss mouse 3T3, we studied the effects of type V collagen on cell adhesion to fibronectin in serum-free medium. When the culture dishes were coated with a mixture of fibronectin with various concentrations of type V collagen, the adhesion of the cells was inhibited depending on the concentration of type V collagen. The inhibition of cell adhesion by type V collagen was competitively overcome by increased concentrations of fibronectin. The activity that interferes with the effects of fibronectin was retained mainly by the alpha 1 chain of heat-denatured type V collagen.
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PMID:Inhibition of cell adhesion by type V collagen. 176 72

The rebuilt tumor model is a three dimensional mass of tumoral cells and angioma fusiform cells in collagen. Rebuilt tumors can give rise to "in vitro metastases" and these metastases depend on the presence of a neomatrix secreted in vitro by rebuilt tumor cells. This study defines the origin of the neomatrix and its role in "in vitro metastasis". Fusiform cells of angioma origin (AF3cells) were stimulated ten-fold by growing them in conditioned medium from a human melanoma cell line (MM2). The stimulated AF3 cells produced a dense neomatrix that was firmly attached to the culture flask. The AF3 cells were removed and MM2 cells were grown on this neomatrix. They gave rise to tumorous nodules very like the "in vitro metastases" produced by rebuilt tumors. The MM2 conditioned medium contained basic fibroblast growth factor, which could account for the angiogenetic activity of the tumoral cells. The fusiform cells of angioma origin that are stimulated by cancerous conditioned medium, are responsible for secretion of the neomatrix which plays a role in "in vitro metastasis".
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PMID:Angioma fusiform cells stimulated by conditioned medium from melanoma cells secrete a neomatrix which plays a role in "in vitro metastasis". 177 23

Local hyperthermia combined with intralesional cisplatin chemotherapy is a logical and potentially effective therapeutic approach for localized cancers. A trial using outbred animals with spontaneously occurring tumours was initiated to evaluate the toxicity and efficacy of this approach. Treatment consisted of injection of a colloidal suspension of cisplatin into the tumour prior to hyperthermia once a week for 4 weeks. Immediately after intratumoral injection of a mixture of cisplatin and collagen, thermotherapy was given. The goal temperature was 42 +/- 1 degrees C for 30 min. Ten animals (nine dogs and one cat) with soft tissue neoplasms were treated with one to four hyperthermia and cisplatin sessions for a total of 30 treatment sessions. Complete responses occurred in 4/10 cases (one carcinoma, two sarcomas, one melanoma). One dog with haemangiopericytoma had partial response. The lack of systemic toxicity and the minimal local normal tissue reactions indicate that the treatments were well tolerated. These data provide preliminary evidence that a combination of local hyperthermia and intratumoral cisplatin chemotherapy is a safe and effective method for the treatment of selected localized neoplasms.
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PMID:Localized thermo-cisplatin therapy: a pilot study in spontaneous canine and feline tumours. 180 42


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