Anchorage-independent growth in soft agar at different oxygen conditions. A: Growth of Ras-LP cells in soft agarat 2% and 21% environmental oxygen. Lowering external oxygen levelsresults in a 3-fold increase in the number of colonies per cm2. *:p < 0.05 (Student's t-test). B: Growth of Ras-HP cells in soft agar at2% and 21% environmental oxygen. Lowering external oxygen levels inRas-HP soft agar cultures results in only a marginal 1.3-fold andnon-significant increase in colony number, showing that a glycolyticshift in these relatively glycolytic cells does not result in a largeincrease in viability and colony formation of cells in the soft agar.