ADVANCES IN TUMOR PREVENTION, DETECTION AND CHARACTERIZATION. III. BIOLOGICAL CHARACTERIZATION OF HUMAN TUMORS

One of the greatest difficulties in establishing permanent cell lines derived from human tumors is the presence of stromal fibroblasts. They show a morphology and growth pattern that may fulfill the criteria, described and established by Hayflick (1965) and others, for normal fibroblasts in vitro. The present investigation was directed at clarifying the in vitro behavior of stromal fibroblasts derived from human lung cancers, in comparison with fibroblasts derived from tissues (skin, kidney, lung) of non neoplastic patients. It was shown that all the fibroblastic strains derived from the lung tumors tested, have undergone a spontaneous transformation, suggesting that these cells were in a preneoplastic state. Strains derived from non neoplastic patients proceeded to the declining stage and did not transform. Some enzymatic and genetic parameters of these cell strains, and of skin fibroblasts derived from neoplastic patients, were evaluated during the different stages of cell life. The results are discussed.