Establishment of a cell line from a human giant cell tumor of bone.

A cell line (CG-1) was established from a specimen of a 21-year-old woman with giant cell tumor of bone. Inverted-phase microscopic analysis showed that the cultured cells were spindle-shaped in appearance. Multinucleated giant cells and macrophagelike round cells characterizing the histology of giant cell tumor of bone were not found. It is believed that the spindle-shaped cells were the neoplastic element of this tumor, because they were cultured more than 40 passages over the course of one year and subsequent cytogenetic analysis with a G-band technique showed constant loss of chromosomes 14 and 19. The cell line was found to produce several cytokines: M-CSF, IFN-gamma and TNF-alpha, as demonstrated by Western blotting analysis. These cytokines are known to show chemotactic, differentiation-inducing, and activating effects on macrophages. Because it has been recently reported in the literature that there are many infiltrated macrophages in giant cell tumor of bone, and because multinucleated giant cells are formed by fusion of macrophages, the newly established cell line may prove a useful system in studying the nature of giant cell tumor of bone.