Die Veränderungen der Häufigkeit euploider und aneuploider Chromosomenzahlen in der hepatektomierten Rattenleber bei Buttergelb-Verfütterung

Karyotypic evolutions of cancer species in rats during the long latent periods after injection of nitrosourea

“…In the following we list parallel rat-, other animal- and human preneoplastic systems, in which persistent proliferative hyperplasias with non-clonal aneuploidies have been observed previously (see also Background ): Studying rat tracheal primary cells 5–6 weeks after a single treatment with nitrosoguanidine Barrett et al observed in 1988 that selection for “enhanced growth” coincided with non-clonal, “abnormal karyotypes” [ 51 ]. Non-clonal aneuploid “hyperplasias” were also observed (a) in rats treated with nitrosamine for 10 weeks in 2009 [ 52 ], (b) in rats treated “early”, from 8 to 57 days with methylcholanthrene in 1975 [ 53 , 54 ], and (c) in rats treated “early”, from 2.5 to 6 months after treatments with azo-dyes and radiation in 1960 and 1963 [ 55 , 56 ] and with butter yellow in 1957 [ 57 ]. Enhanced or hyperplastic growth segregating with non-clonal aneuploidy was also observed (a) by Levan in spontaneously transforming mouse cells in vitro in 1958 [ 10 ], (b) and by Hauschka in carcinogen-treated mice, “One of the first precancerous reactions was the appearance of numerous mitotic abnormalities with a frequency of up to 60 percent” [ 21 ] and (c) by Nowell in cells of irradiated mice, “… with extensive chromosome changes [that] may persist in the hematopoietic tissues for long periods after irradiation without leukemia arising” [ 22 ].…”

“…Studying rat tracheal primary cells 5–6 weeks after a single treatment with nitrosoguanidine Barrett et al observed in 1988 that selection for “enhanced growth” coincided with non-clonal, “abnormal karyotypes” [ 51 ]. Non-clonal aneuploid “hyperplasias” were also observed (a) in rats treated with nitrosamine for 10 weeks in 2009 [ 52 ], (b) in rats treated “early”, from 8 to 57 days with methylcholanthrene in 1975 [ 53 , 54 ], and (c) in rats treated “early”, from 2.5 to 6 months after treatments with azo-dyes and radiation in 1960 and 1963 [ 55 , 56 ] and with butter yellow in 1957 [ 57 ].…”

Aneuploidy, the somatic mutation that makes cancer a species of its own

“…All cancers caused by non-genotoxic carcinogens should be diploid. But this is not observed in experimental cancers [Marquardt and Glaess, 1957;Oshimura and Barrett, 1986;Li et al, 1997;Duesberg et al, 1998]. 2.…”

Is carcinogenesis a form of speciation?

“…butter yellow in 1957, 121 (d) "preneoplastic lesions" of mice treated with dimethylbenzanthracene either in the liver, spleen, thymus 122 or the skin in the form of precancerous papillomas, 123 (e) livers of rats treated with nitrosamine and other chemicals that induce liver cancer "to identify the importance of chromosome versus genome mutations," 124 (f) hyperplastic mammary tissue of rats treated with dimethylbenzanthracene to induce mammary cancer, 125 (g) "transformed" Syrian hamsters cells treated with carcinogens in vitro, 34 and (h) spontaneously transformed mouse and Chinese hamster cells growing in vitro prior to acquiring tumorigenicity. 126,127 New experimental tests of the long latencies between induction of aneuploidy and carcinogenesis.…”