Lactate Dehydrogenase

Lactate Dehydrogenase (LDH) is an enzyme that catalyzes the conversion of pyruvate, the end product of glycolysis, into lactate (and vice versa) with concomitant interconversion of NADH and NAD⁺. LDH is comprised of two major subunits, LDH-A and LDH-B, which can assemble into five different isoenzymes (LDH1, LDH2, LDH3, LDH4, and LDH5).

LDH-A is also known as the M subunit as it is predominantly found in skeletal muscle, and LDH-B is also known as the H subunit as it is predominantly found in the heart. LDH-A is a vital metabolic enzyme that is associated with cancer development, invasion, and metastasis. LDH-A is also the key player of the Warburg effect. LDH-A has been reported to correlate with clinicopathologic characteristics and survival outcome of multiple cancers. The inhibition of LDH-A has an anti-proliferative effect on primary breast tumors. LDH-B is a crucial glycolytic enzyme that catalyses conversion of lactate and NAD⁺ to pyruvate, NADH and H⁺. LDHB plays an important role in autophagy in cancer cells.