Cytological study with reference to malignancy on clonal cell lines of a mouse fibrosarcoma.

Abstract

AbstractSeveral clonal and subclonal cell lines have been developed from a low tumorigenic Swiss mouse sarcoma cell strain MFS8 in its 200th passage of cultivation. Clonal line 3 (Cl3) and its subclone 20 (SCl20) are the only cell lines that developed tumours on inoculation into the same strain host. These two malignant clones are therefore compared with their non‐malignant sister clones derived from the same parental stock.Significant differences were noted in the biological characters of malignant and non‐malignant clones. Both malignant clones displayed high growth rate, higher morphologic and cytologic uniformity, a more homogeneous set of marker chromosomes (90%) with consistency in the occurrence of special dicentric marker “A” and lower frequency of mitotic abnormalities as against the sister clones. The stem line number of chromosomes was also in the narrowest diploid range and mitotic abnormalities were least in the malignant clones. Much better balance and uniformity of biological characters and better viability in vitro were thus observed in the tumour‐producing clonal lines as compared with the non‐tumour clonal lines. The significance of the data is discussed.