Specific chromosome changes associated with viral transformation of rat glial cells.
Karyotypes of three malignant cell lines derived from Wistar and WKA/Mk fetal rat glioblasts, transformed by murine sarcoma virus (MSV-M-os) as well as those of four cell lines derived from C6 glioma cells of Wistar origin, retransformed by MSV-M-os, were analyzed in early culture passages. The C6 line had a modal number of 42 chromosomes with a normal male karyotype, and only a minor population of cells with 43 chromosomes. The modal chromosome number in every transformed glial cell line shifted from 42 to 43. The G-banding pattern revealed consistent chromosome abnormalities. Structural chromosome changes occurred in one chromosome No. 2 (2q-) and in one No. 4 (4q+). The cells with a 43 chromosome karyotype showed trisomy of chromosome No. 12 and its heteromorphism, a finding also confirmed by silver staining. Identical chromosome changes were found in transformed C6 cell lines. A further interesting feature was that all malignant cells had different distribution patterns of silver-stained nucleolar organizer regions (Ag-NORs) among particular chromosomes (Nos. 3, 11 and 12) from normal cells, showing an increased frequency of chromosome No. 12 with Ag-NORs. These results suggested that the gain and/or loss of specific segments involved in chromosomes Nos. 2, 4 and 12 contain(s) genes favorable to malignant transformation in rat glial cells.
D000818:Animals; D002460:Cell Line; D002472:Cell Transformation, Viral; D002478:Cells, Cultured; D002869:Chromosome Aberrations; D002871:Chromosome Banding; D002875:Chromosomes / Q000502:physiology*; D005910:Glioma / Q000235:genetics / Q000382:microbiology*; D007621:Karyotyping; D009132:Muscles / Q000382:microbiology; D009457:Neuroglia / Q000382:microbiology*; D051381:Rats