We demonstrated that the Kirsten murine sarcoma virus (KiMSV) and the Harvey murine sarcoma virus (HaMSV) converted human skin fibroblasts (HSF) into adipocytes. Adipocytic conversion of HSF by KiMSV and HaMSV was dependent on the presence of glucocorticosteroids. The Kirsten murine leukemia virus, the Harvey murine leukemia virus and the amphotropic helper virus (AP292) were ineffective by themselves. Balb murine sarcoma virus and Moloney murine sarcoma virus were, to a lesser degree, able to effect adipocytic conversion of HSF. In contrast, the feline sarcoma virus and the simian sarcoma virus did not cause this conversion. Together, the results suggest a role for certain oncogenes and glucocorticosteroids in the transformation/neodifferentiation of human cells.
We have determined the sensitivity to 5-azacytidine of cultured fibroblasts obtained from clinically defined areas on the skin of patients with hereditary adenomatosis of the colon and rectum (ACR) and von Recklinghausen neurofibromatosis (NF). Fibroblasts from normal appearing skin of both ACR and NF patients were about 2- to 3-fold more resistant to 5-azacytidine-induced cytotoxicity than were fibroblasts obtained from comparable areas of normal persons. Fibroblasts from café-au-lait lesions and from neurofibromas (NF) were increasingly more resistant to 5-azacytidine than were fibroblasts taken from normal appearing skin of the same NF patient as well as of patients from different pedigrees. The results show that fibroblasts from persons predisposed to cancer and from cancer-prone tissues in such persons are abnormally resistant to 5-azacytidine as determined by the cloning efficiency assay.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.