Establishment and characterization of a new murine mammary tumor cell line, BALB/c-MC.

A new murine mammary tumor cell line (BALB/c-MC) was established from a spontaneous mammary tumor in a 17-mo.-old female mouse of the low mammary cancer strain BALB/cHe. The cell line was derived from a papillary adenocarcinoma. In monolayer culture the line exhibits a pavementlike arrangement of cells and forms "domes" or "hemicysts" as the cells become confluent. The cell line rapidly forms tumors when transplanted into young syngeneic BALB/cHe mice. The subcutaneous injection of 10(6) cells resulted in the development of mammary tumors (typical papillary adenocarcinomas) in 33 of 37 (87%) recipients within 2 to 3 mo. after injection. These mammary tumors also metastasize to lung [14 of 33 (42%) of recipients] during this time. The number of chromosomes in this cell line is hyperdiploid (average of 43, range 39 to 44).