Cultivation of Human Breast Carcinomas2

A method was developed for the cultivation of human breast carcinoma cells. This technique, taking advantage of the weak intercellular bonds within the tumor, harvests the cells “spilling” out of the tumor stroma when thin slices are cut with a razor blade. This suspension was sensitive to customary enzymatic concentrations which therefore cannot be used in the preliminary step of preparation. Agitation, even the slow motion of the roller drum, was unfavorable to the growth of the neoplastic cells which have to be explanted in resting tubes. Continuous cultivation of human breast carcinoma cells was achieved for the first time. The cultures, derived from a mammary duct-cell carcinoma of no special type, are now in their 6th month of life in vitro and extremely proliferative. A regular growth rate of the neoplastic cells appeared to be dependent on the presence in the medium of mucopolysaccharides introduced in the form of umbilical-cord extract. Human placental serum and beef amniotic fluid, whose high content in estrogenic hormones is well known, also had a beneficial effect. Folic acid in a 2.5 mM concentration appeared favorable to the growth of the cancer cells. However, a possible antagonism with cord extract was considered in relation to the spindle-shaped transformation which occurred in the epithelial cells when transferred from a folic acid medium to one enriched with cord extract.