Biomaterial Database

Tumorigenicity of human malignant melanocytes in nude mice in relation to their differentiation in vitro. 1980

C Aubert, and F Rougé, and J R Galindo

Of 16 cell lines derived from 12 human melanomas obtained from 11 patients, all were established as permanent cell lines: 7 from primary tumors and 9 from metastatic tumors. Study of the early subcultures and established cell lines showed that melanocytes passed through a phase of dedifferentiation during which they took on a fibroblast-like appearance and were hypodiploid and nontumorigenic in nude (thymus-deficient) mice. Phenotypic modulation in vitro was shown to be dependent on the culture medium. The lines varied considerably in karyologic and phenotypic expression (as assessed by morphologic appearance and 5-S-cysteinyldopa production). Fibroblast-like, epithelioid, nonpigmented, achromic, and pigmented cells were obtained from the same tumor. Heterotransplantation into nude mice revealed wide variations in tumorigenicity: The latency of the tumors, their size, and infrequent metastases bore no relationship to the phenotypic modulation of the melanocytes as expressed in vitro. Melanogenesis is therefore not related to malignancy; they are two independent characteristics.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D008544	Melanocytes	Mammalian pigment cells that produce MELANINS, pigments found mainly in the EPIDERMIS, but also in the eyes and the hair, by a process called melanogenesis. Coloration can be altered by the number of melanocytes or the amount of pigment produced and stored in the organelles called MELANOSOMES. The large non-mammalian melanin-containing cells are called MELANOPHORES.	Melanocyte
D008545	Melanoma	A malignant neoplasm derived from cells that are capable of forming melanin, which may occur in the skin of any part of the body, in the eye, or, rarely, in the mucous membranes of the genitalia, anus, oral cavity, or other sites. It occurs mostly in adults and may originate de novo or from a pigmented nevus or malignant lentigo. Melanomas frequently metastasize widely, and the regional lymph nodes, liver, lungs, and brain are likely to be involved. The incidence of malignant skin melanomas is rising rapidly in all parts of the world. (Stedman, 25th ed; from Rook et al., Textbook of Dermatology, 4th ed, p2445)	Malignant Melanoma,Malignant Melanomas,Melanoma, Malignant,Melanomas,Melanomas, Malignant
D008819	Mice, Nude	Mutant mice homozygous for the recessive gene "nude" which fail to develop a thymus. They are useful in tumor studies and studies on immune responses.	Athymic Mice,Mice, Athymic,Nude Mice,Mouse, Athymic,Mouse, Nude,Athymic Mouse,Nude Mouse
D008854	Microscopy, Electron	Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.	Electron Microscopy
D009362	Neoplasm Metastasis	The transfer of a neoplasm from one organ or part of the body to another remote from the primary site.	Metastase,Metastasis,Metastases, Neoplasm,Metastasis, Neoplasm,Neoplasm Metastases,Metastases
D009368	Neoplasm Transplantation	Experimental transplantation of neoplasms in laboratory animals for research purposes.	Transplantation, Neoplasm,Neoplasm Transplantations,Transplantations, Neoplasm
D009374	Neoplasms, Experimental	Experimentally induced new abnormal growth of TISSUES in animals to provide models for studying human neoplasms.	Experimental Neoplasms,Experimental Neoplasm,Neoplasm, Experimental
D010641	Phenotype	The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.	Phenotypes
D002454	Cell Differentiation	Progressive restriction of the developmental potential and increasing specialization of function that leads to the formation of specialized cells, tissues, and organs.	Differentiation, Cell,Cell Differentiations,Differentiations, Cell