Pharmacologic assessment of regimen chemosensitivity in the soft-agar assay: Effect of oxygen on human tumors

The influence of oxygen on the growth and the in vitro chemosensitivity of human tumor cells was studied in the soft-agar assay. Tumor cells of pancreatic and ovarian origin prefer a reduced oxygen atmosphere for colony formation, whereas those of pulmonary origin grow better in 20% oxygen. Depending on the physiologic oxygen tension and the histologic origin of a particular cancer type, the in vitro chemosensitivity of many drugs obtained with the conventional culture system could be inadequately assessed.