Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0027960 (mole)
 21,279 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Infection of normal human melanocyte and nevus cultures with an adenovirus 12-Simian Virus 40 hybrid virus (Ad12-SV40) produced transformed cells that expressed SV40-T antigen. The Ad12-SV40 cells exhibited rapid cell proliferation to high cell densities and efficient growth in soft agar, but none of 15 transformed melanocyte and nevus cultures formed tumors when injected s.c. or under the renal capsule into athymic nude mice. While the Ad12-SV40-transformed cells lost certain properties associated with the melanocytic phenotype, i.e., pigmentation, tyrosinase activity and melanosome content, the expression of melanoma-associated antigens, including nerve growth factor receptor, p97 melano-transferrin, and chondroitin sulfate proteoglycan, remained stable. The transformed melanocytes acquired the ability to express HLA-DR antigen, which is found on nevus and melanoma cells. Total ganglioside patterns in Ad12-SV40-transformed cells changed to reflect more advanced stages of tumor progression. Transformed melanocytes, like nevus and melanoma cells, showed increased GD3 content and transformed nevus cells increased GD2 which is a feature of malignant melanoma cells. Ad12-SV40-transformed human melanocytes and nevus cells are useful tools for studying tumor progression under experimental conditions.
 ...
PMID:Transformation of normal human melanocytes and non-malignant nevus cells by adenovirus 12-SV40 hybrid virus. 255 80

Nevus cells were isolated from the three cutaneous components, epidermis, basal layer, and dermis, of nonmalignant pigmented lesions and were cultured separately in the presence or absence of the phorbol ester 12-0-tetradecanoyl phorbol-13-acetate in medium that supports the rapid proliferation of melanocytic cells. The separation procedure used provided cultures that were essentially free from normal melanocytes (dermis) or fibroblasts (epidermis). In short term culture, nevus cells of all skin compartments expressed markers associated with differentiated melanocytes, such as presence of premelanosomes and melanosomes and elevated tyrosinase levels. Nevus cells also expressed melanoma-associated antigens, such as NGF-receptor, transferrin-related p97, proteoglycan, and HLA-DR as detected with monoclonal antibodies. After several subpassages, cells showed a decreased expression of melanoma-associated antigens, decreased tyrrosinase levels, and melanosomes could no longer be detected. Morphologically, these cells were similar to fibroblasts. The disappearance of melanoma-associated cell surface antigens was concomitant with the appearance of a melanocyte-associated 145 kd protein that might serve as a marker of fibroblast-like differentiation in nevus cells and normal melanocytes. Nevus cell cultures grown in the presence of 12-0-tetradecanoyl phorbol-13-acetate maintained a stable differentiated phenotype throughout their lifespan. As reported earlier, nevus cells in culture, irrespective of the presence or absence of 12-0-tetradecanoyl phorbol-13-acetate, have a finite lifespan in vitro, grow anchorage-independent in soft agar, but do not form tumors when xenografted to nude mice. These studies demonstrate that nevus cells isolated from the epidermal, basal layer, and dermal components of lesional skin can serve as models to characterize the initial steps of tumor progression in a human cell system.
 ...
PMID:Growth and phenotypic characteristics of human nevus cells in culture. 282 80

An indirect immunofluorescence technique was used to study the tissue distribution of the epitope recognized by the monoclonal antibody 140.240 which identifies a p97-like melanoma-associated oncofetal antigen. Cryostat sections of various normal and neoplastic human tissues were examined. The presence of antigenic activity was demonstrated in 20 of 39 (51%) primary skin melanomas, in 21 of 52 (40%) metastatic melanomas, and in 20 of 44 (45%) nevi. The reactive nevi were restricted to intradermal, junctional, compound and spindle cell types. Of the 110 samples of 12 major tumor types other than melanoma tested, only 1 of 6 epidermoid tumors, 1 of 4 benign breast tumors and 1 of 5 prostatic tumors gave weak staining. This antibody also reacted with sweat glands and fetal small intestine tissue, but not with other adult or fetal normal tissues. Intrapatient as well as interpatient heterogeneity in the epitope expression was present in primary as well as metastatic tumor lesions surgically removed from patients with melanoma. Evaluation of the immunohistologic data and the clinical outcome of patients with melanoma reveals that the expression of the epitope recognized by this antibody is associated with a more favorable prognosis.
 ...
PMID:Immunohistochemical detection of antigen in human primary and metastatic melanomas by the monoclonal antibody 140.240 and its possible prognostic significance. 353 8

Monoclonal antibodies (mAb) were selected for differential binding to sections of freshly frozen biopsy material of human malignant melanomas and their precursor lesions, the melanocytic nevi. Both melanomas and normal nevi expressed human Ia-like antigens, transferrin receptor and the transferrin-related molecule p97. In contrast, only 1 nevus of 21 tested expressed both glycoprotein gp75, defined by mAb 15.75, and protein p89, defined by mAb P3.58, whereas 12 of 15 melanomas tested expressed both antigens. mAb P3.58 reacted with one additional melanoma and one nevus. The expression of these two molecules therefore appears to be correlated with the appearance of the malignant phenotype of melanocytes.
 ...
PMID:In situ analysis of antigens on malignant and benign cells of the melanocyte lineage. Differential expression of two surface molecules, gp75 and p89. 397 33