Neoplastic Transformations in C3H Mouse Embryonic Tissue In Vitro Determined by Intraocular Growth. I. Cells From Chemically Defined Medium With and Without Serum Supplement

Publisher Website
Google Scholar
Abstract
Tissue from minced C3H mouse embryos was cultured in both chemically defined medium NCTC 109 alone and supplemented with 10 percent v/v horse serum. In the serum-supplemented medium, in vitro neoplastic transformations were biologically verified by intraocular and intramuscular implants of three series of the tissue. The cells used for implants were cultivated for 28 to 541 days. Cells of the first series cultured for 176 days produced grossly observable growths. The second and third series required 147 and 124 days, although histologically a fibrosarcoma was obtained from cells of the second series only 121 days in vitro. On implantation, cells 117 days in vitro in the third series failed to produce tumors; apparently an alteration occurred within 1 week. The ability of cells to produce tumors was preceded by an increased rate of proliferation in cultures. These tumors were composed predominantly of fusiform cells and occasionally had inclusions of cartilage and bone. Because fusiform fibroblastic cells predominated, the tumors were designated fibrosarcomas. The period between implantation of cells from cultures and appearance of the tumors shortened with increased time in vitro. Several tumor transplants produced rapidly growing fibrosarcomas within 13 to 145 days. Cultures grown on chemically defined medium NCTC 109 alone have been kept alive in vitro over 19 months. No progressively growing tumors appeared from a limited number of intraocular implants from these cultures. Early resorption or small growths occurred; these adhered to the cornea for a short period and then slowly regressed. Some sections showed small areas of ossification, but no neoplastic areas were observed. The reproducibility of time of occurrence and nature of the response in this study suggests the suitability of the system for pursuing studies of neoplastic transformations in vitro.