Cytogenetic analysis of collagenase- releasing rabbit VX-2 carcinoma-derived cells.
Primary cultures of rabbit VX-2 carcinoma appeared to be heterogeneous, containing at least two morphologically distinct cell types, fibroblast-like cells (F cells) and epithelioid cells (E cells). Ultrastructural studies suggested that the E cells were of epithelial origin, whereas the F cells did not differ significantly from normal rabbit fibroblasts. Cytogenetic studies showed that the E cells were characterized by numerical and structural chromosomal changes which remained constant subsequent to serial in vitro culture and in vivo transplants in rabbits. Analysis of G-banded chromosomes from E cells revealed a modal number of 54 with relatively few normal chromosomes and a variety of distinctive, mostly unidentifiable marker chromosomes. The origin of only four marker chromosomes could be partially determined. The ratio of normal to marker chromosomes remained relatively constant following serial transplants in rabbits. The F cells appeared to be derived mainly from host tissue, as they contained a normal diploid complement with sex chromosomes corresponding to the sex of the host.