HIF1A and neoplasm: Immunohistochemical analysis of human colorectal adenocarcinomas showed that tumour cells express high levels of GLUT1, MCT1, and HIF-1α, indicating increased anaerobic metabolism and lactate production, whereas the expression profile of CAFs (low level of GLUT1/HIF-1α, and high MCT1/MCT2) suggested high lactate absorption and oxidative metabolism [142].