Lymphocytes from four patients with NF and from four normal controls are studied for SCEs and the cell cycle kinetics in the MMC-treated cultures. The result reveals that NF lymphocytes have almost the same proliferative kinetics and SCE frequencies as normal cells both in untreated cultures and when exposed to MMC.
The karyotypes of two malignant cell lines, GA1 and GA2, derived from chemically transformed glioblasts of WKA and BDIX rats, respectively, were investigated by G-banding at early passage numbers. In GA1, the karyotype 43; XY, 2q-, 4q+ and 12 trisomy, predominated and the cells with an additional 10p+ were less frequently observed. These consistent chromosomal changes were exactly identical with those previously found in virus-induced glioblast lines. GA2 had the normal male diploid stemline although a minor population of cells having the GA1-karyotype was also present. Thus, the present results combined with prior findings indicated that the in vitro transformed rat glial cells showed the common and specific changes in the karyotype regardless of the type of the oncogenic agent and rat strain.
Ag-NORs in two GA cell lines, derived from chemically transformed glioblasts of WKA and BDIX rats were investigated. The distribution patterns of Ag-NORs among chromosomes nos. 3, 11 and 12 in normal glioblasts varied between two rat strains. The Ag-NOR pattern in GA cell lines, on the other hand, was different from the respective normal one but it was similar between two cells. The identical NOR abnormalities have also been observed in the virus-transformed glial cells. The results combined from both studies showed that specific changes in the Ag-NOR pattern are associated with in vitro transformation of rat glioblasts regardless of the type of the carcinogenic agent, rat strain as well as the karyotype.