1 Introduction.- 2 Are Cancer Cells Malignant Per Se?.- 3 Cell Growth: A Balance Between Glycolysis and Physical Constraint.- 4 Extracellular Constraints Regulate Cell Differentiation.- 5 Extracellular Constraints Regulate Cell Differentiation.- 6 Hypoxia Is Responsible for Changes in Cellular Constraints During Inflammation.- 7 Fibrosis Perpetuates Hypoxia.- 8 Metastasis: The Hunt for Food.- 9 Carcinogens Target Cell Respiration and Induce Glycolysis.- 10 Epidemiology: Aging as the Main Cause of Cancer.- 11 Aging Causes Inflammation and Fibrosis Mimicking the Impact of Carcinogens.- 12 Inhibition of Metabolism Slows Aging and Decreases Cancer Incidence.- 13 A Complication of Hypoxia: The Loss of Cell Polarity Explains Cancer Cell Proliferation.- 14 The Loss of Cell Differentiation Is a Consequence of Glycolysis.- 15 Response to Treatment: A Balance Between Glycolysis and Physical Constraints.- 16 Targeting Glycolysis.- 17 Conclusion.