The phenomenon of cancer cells switching to glycolysis even in the presence of adequate oxygen for oxidative phosphorylation is known as:

Even in the presence of ample oxygen, cancer cells shift their glucose metabolism away from the oxygen hungry, but efficient, mitochondria to glycolysis. This phenomenon, called the Warburg effect and also known as aerobic glycolysis, has been recognized for many years (indeed, Otto Warburg received the Nobel Prize for discovery of the effect that bears his name in 1931), but was largely neglected until recently. This metabolic alteration is so common to tumors that some would call it the eighth hallmark of cancer. Ref: Robbins 8th edition Chapter 2.