Chinese hamster ovary cell transformations

The genotoxic data are largely negative, although 1,1,1-trichloroethane was mutagenic in some Salrmnella assays and induced chromosomal aberrations in Chinese hamster ovary cells and cell transformation in mammalian systems. ... 

Cell transformation, baby hamster kidney BHK-21 cells Cell transformation, Chinese hamster ovary cells... 

Unscheduled DNA synthesis, rat primary hepatocytes in vitro Sister chromatid exchange, Chinese hamster ovary cells in vitro° Chromosomal aberrations, Chinese hamster ovary cells in vitro Cell transformation, BALB/c 3T3 mouse eells ... 

Chromosomal aberrations were not induced in rat liver cells, Chinese hamster lung cells or Chinese hamster ovary cells by in-vitro exposure to triethanolamine. It did not induce cell transformation in Syrian hamster embryo cells. 

Tetrachloroethane did not induce chromosomal aberrations in Chinese hamster ovary cells. It induced sister chromatid exchanges in Chinese hamster ovary and mouse BALB/c 3T3 cell cultures and cell transformation in BALB/c 3T3 cells in vitro. 

Trichloroethane did not induce unscheduled DNA synthesis in rat primary hepatocytes. It showed inconclusive evidence of gene mutation at the tk locus in mouse lymphoma L5178Y cells in the presence of an exogenous metabolic activation system. Results for induction of sister chromatid exchanges were also inconclusive. 1,1,1-Trichloroethane increased the frequency of chromosomal aberrations in Chinese hamster ovary cell cultures and induced morphological transformation in BALB/c 3T3 and in Fischer rat and virally-enhanced Syrian hamster embryo cells in vitro. 

Tetrachloroethane induced gene mutations in the mouse lymphoma tH -assay only in the presence of an exogenous metabolic activation system. It did not increase the frequency of chromosomal aberrations in Chinese hamster lung fibroblasts or ovary cells but did induce sister chromatid exchanges in Chinese hamster ovary cells and aneuploidy in Chinese hamster lung fibroblasts in the absence of exogenous activation. 1,1,1,2-Tetrachloroethane did not induce cell transformation in BALB/C-3T3 cells. 

Chloroethane was mutagenic to bacteria and at the hprt locus in a study with the Chinese hamster ovary cell line, but not did not induce transformation in BALB/c 3T3 cells. In B6C3F] mice exposed by inhalation, it did not induce either unscheduled DNA synthesis in hepatocytes or micronuclei in bone-marrow cells. 

Several bacterial and mammalian short-term tests for genetic toxicity as well as their biochemical and genetic rationale are described in Chapter 21 on toxicity testing. They include the salmonella assay, the Chinese hamster ovary cell/hypoxanthine-guanine phosphoribosyl transferase assay, the mouse lymphoma assay, the mammalian transformation assay, sister chromatid exchange, and the chromosome aberration assay. 

Giancotti, F. G. and Ruoslahti, E. (1990). Elevated levels of the alpha 5 beta 1 fibronectin receptor suppress the transformed phenotype of Chinese hamster ovary cells. 60, 849-859. 

In mammalian cells in vitro, it induced DNA strand breaks, gene mutations in mouse lymphoma cells (without activation) but not in Chinese hamster ovary cells, and a low frequency of sister chromatid exchange but not of chromosomal aberrations in Chinese hamster ovary cells. It inhibited intercellular communication but did not induce cell transformation. 

Yamaguchi and Ruoslahti (71) first noted that overexpression of decorin in Chinese hamster ovary cells reduced their rate of proliferation and density at saturation. This effect was subsequently attributed to the direct binding and inactivation by decorin of the transforming growth factor-(3 (TGF-p) that was considered to be an autocrine stimulator of cell proliferation in these cultures (72). Biglycan was also reported to bind to TGF-p in the solid-phase competition assay system used in this study. 

There are few data on clastogenic effects of tetrachloroethylene following in vitro exposure. When Chinese hamster ovary cells were assayed for sister chromatid exchanges, no increase in frequency was found (NTP 1986). Two assays of cell transformation in mouse cells treated with tetrachloroethylene were negative (NTP 1986 Tu et al. 1985). However, Fischer rat embryo cells were transformed in the absence of metabolic activation. 

The aqueous extracts of U. tomentosa showed the significant inhibitory activity against human leukemia cancer ceU fines (K562 and HL 60) and a human EBV-transformed B l3mphoma ceU line. Literature revealed that the extract of this plant-induced apoptosis, in conjugation with DNA fragmentation, which evidences the antitumor activity [38,37], The aqueous extract of this plant had also been tested for toxicity against Chinese hamster ovary cells, which revealed that it is nontoxic at low concentrations [62],... 

Dioxane with or w ithout metabolic activation did not induce differential DNA repair in Escherichia coli K-12 uvrB/rec A and was not mutagenic in Salmonella typhimurium or in L5178Y mouse lymphoma cells. In Chinese hamster ovary CHO cells, it did not cause chromosomal aberrations, although it did cause a slight increase in sister chromatid exchange in the absence of metabolic activation. It has also been reported to cause morphological transformation of BALB/c 3T3 mouse cells. 

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