Multiple chromosomes carrying tumor suppressor activity, via microcell-mediated chromosome transfer, for various tumor cell lines.

The ability of normal human fibroblast-derived chromosomes to suppress tumorigenicity in nude mice and in vitro growth properties of various tumor cell lines was examined. Normal human chromosomes tagged with pSV2neo gene by DNA transfection were transferred to the following human tumor cell lines by microcell-fusion: SiHa (uterine cervical carcinoma), A204 (rhabdomyosarcoma), SK-NEP-1 (Wilms' tumor), HHUA (uterine endometrial carcinoma), SK-N-MC (neuroblastoma), YCR (renal cell carcinoma), HT1080 (fibrosarcoma), and CC1 (chorionic carcinoma). The results indicate the presence of a putative tumor-suppressor gene(s) in multiple chromosomes, and suggest that multiple genes may normally be involved in suppressing the transformed phenotypes at different stages in some tumors. Thus, the microcell transfer of chromosomes to specific tumor cell lines is a useful technique to demonstrate the presence of tumor-suppressor genes on individual chromosomes, and may also be useful in cloning of tumor-suppressor genes as well as elucidating their function in cell-growth and differentiation.