Transformation assay morphological

Water-soluble nickel salts enter the cells with relative ease but are less effective than crystalline particulates in the cell transformation assay, when using hamster cells [429, 430]. However, an enhancement of viral transformation of cells has been found [431, 432], In addition, a synergistic effect of cigarette smoke extracts, benzo[a]pyrene and nickel sulphate on the morphological transformation of hamster embryo cells has also been obtained [433], It was suggested that nickel salts are more potent as promoters than they are as initiators [434],... 

The SHE cell transformation assay at pH 6.7 is conducted to determine the ability of a test article to induce morphological transformation in cultured SHE cells. The SHE cell transformation assay is one of the most widely used cell transformation assays. The endpoints of this assay are related to the conversion of normal cells into preneoplastic or neoplastic cells. The assay provides a valuable tool in the process of assessment and evaluation of the carcinogenic potential of a test article.2 28... 

RLV/Fischer rat assay without the addition of an exogenous metabolic activation system. In a single study, mouse JB6 epidermal cells were transformed by di(2-ethyl-hexyl) phthalate without activation and in one of two studies a weak response was reported in the CSHIOT A cell transformation assay with di(2-ethylhexyl) phthalate in either the absence or presence of exogenous metabolic activation. BALB/c-3T3 cells were not transformed by di(2-ethylhexyl) phthalate with or without metabolic activation. Di(2-ethylhexyl) phthalate inhibited gap-junctional intercellular communication in Chinese hamster V79 cells in six of seven studies, but not in one study of liver cells of cynomolgus monkeys in vivo. Di(2-ethylhexyl) phthalate treatment of Syrian hamster embryo cells in a two-stage exposure with 12-O-tetradecanoylphorbol 13-acetate resulted in superinduction of ornithine decarboxylase, an early event in morphological transformation no effect was seen after a one-stage treatment with di(2-ethylhexyl) phthalate alone. 

Syrian hamster embryo (SHE) cell transformation assay (In vitro) (SHE cells are used to evaluate the potential of a wide range of agents to induce morphological transformations. Following carcinogen exposure (1-7 days), SHE cells display a multistage pattern of neoplastic progression similar to that observed in vivo)... 

Progesterone induces characteristic morphological changes of the endometrium after estrogen-induced proliferation of this tissue. This effect is the basis of the endometrium transformation assay, in which immature rabbits are primed with estradiol for several days and are subsequently treated with a progestin, either by oral application or by subcutaneous injection. The proliferating response of the uterus is examined by histological analysis and quantitated with the McPhail index on a scale from 1 to 4, with 4 as maximal effect. The assay is very sensitive and specific, even if the rabbit expresses only the B isoform of PR. 

Pouchus, Y.F., Dauvergne, S., Morel, D., Mondeguer, F., Marcaillou-Lebaut, C., Amzil, Z., and Verbist, J.F. (1998) Combined use of analytical high-performance liquid chromatography and cell morphology transformation assay to detect new protein phosphatase inhibitors okadaic acid type. Toxicon, 36, 383—389. 

Lawrence N, McGregor DB. 1985. Assays for the induction of morphological transformation in C3H/10T1/2 cells in culture with and without S9-mediated metabolic activation. In Ashby J, de Serres FJ, et al., eds. Progress in mutation research. Vol. 5. Evaluation of short-term tests for carcinogens. Amsterdam, The Netherlands Elsevier Science Publishers, 651-658. 

Other assays are being explored in HTS platforms to identify potential inhibitors of invasion, for example, compounds that affect the shape or morphology of cells or their ability to generate invadopodia. Quintavalle et al. recently described such a method initially using Src-transformed NIH 3T3 fibroblasts grown on 384-well optical plates. Imaging of cellular and nuclear morphology combined with phalloidin-stained F-actin was used to discriminate compounds which reduced (or enhanced) the number of... 

Marayama, H., Tanaka, T. Williams, GM. (1990) Effects of the peroxisome proliferator di(2-ethylhexyl)phthalate on enzymes in rat liver and on carcinogen-induced liver altered foci in comparison to the promoter phenobarbital Toxicol. Pathol., 18, 257-267 Matsushima, T, Muramatsu, M. Haresaku, M. (1985) Mutation tests on Salmonella typhimurium by the preincubation method. Prog. Mutat. Res., 5, 181-186 Matthews, E.J., DelBalzo, T. Rundell, J.O. (1985) Assays for morphological transformation and mutation to ouabain resistance of Balb/c-3T3 cells in culture. Prog. Mutat. Res., 5, 639-650... 

Mattliews, E. J., Delbalzo, T. Rimdell, J. O. (1985) Assays for morphological transformation and mutation to ouabain resistance of Balb/c-3T3 cells in culture. Prog. Mutat. Res., 5, 639-... 

Phenotype-based screens ar e essential to assay small synthetic molecules and more complex substances for biological activity, such as the enhancement or suppression of a particular phenotype. Tlie different states may be morphologically identifiable, such as the spindly patliologic morphology of cells transformed with oncogenes v-ras and v-src. Tlie patliologic state is reverted by depudecin into the wild-type state. 

Many tumor viruses do not destroy cells in which they multiply and hence produce no plaques. They induce morphological changes and faster multiplication rate in the infected cells which are known as transformed cells. Colonies of the transformed cells are developed into large foci which are visible by naked eye. Assay by focus formation depends on counting the number of focus-forming units (FFU), which is analogous to plaque formation assay. 

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