As described above, the biochemical phenotype characterized by the upregulation of glycolytic enzymes such as LDH-A and increased lactate production is an essential component of the metabolic reprogramming of tumor cells for the majority of human malignancies and BC in particular, involving the contribution at the cellular level from clinically relevant oncogenic molecular lesions such as HER2 [112,113,114]. The gene discussed is LDHA; the disease is neoplasm.