CA9 and prostate intraepithelial neoplasia: Figure 1A shows the immunohistochemical expression of MCT1, MCT4, glucose transporter 1 (GLUT1), hexokinase 2 (HK2), lactate dehydrogenase 5 (LDH5), pyruvate dehydrogenase kinase 1 (PDK1), carbonic anhydrase IX (CAIX) and hypoxia‐inducible factor 1α (HIF‐1α) in benign prostate tissue (BT), prostatic intra‐epithelial neoplasia (PIN), localized prostate tumour tissue (LT) and metastatic tumour tissue (MT).