Aldehyde dehydrogenase X, mitochondrial (ALDH1B1)

Aldehyde dehydrogenase X, mitochondrial (ALDH1B1) is a mitochondrial enzyme belonging to the aldehyde dehydrogenase superfamily. ALDH1B1 catalyzes the oxidation of a broad spectrum of aldehydes, including acetaldehyde, with a high affinity comparable to ALDH2, using NAD+ as a cofactor. Highly expressed in the liver, intestine, pancreas, and, to a lesser extent, in lung and colon, ALDH1B1 plays a significant role in ethanol metabolism and general detoxification of endogenous and exogenous aldehydes. Recent research positions ALDH1B1 as a marker for stem/progenitor cells in the adult pancreas and colon and as a potential biomarker in multiple human cancers, especially colorectal adenocarcinoma, where its expression is robustly elevated compared to normal tissue. There is also evidence that ALDH1B1 may be required for tumor development in certain oncogenic pathways, notably KRAS-driven pancreatic cancer. Inhibition (for example, by disulfiram) could be therapeutically relevant but poses challenges due to the enzyme’s physiological roles in normal tissues.

Other names

ALDH1B1ALDH5ALDHX

Enzymatic oxidation of aldehydes to carboxylic acids using NAD+ as cofactor; Targeted inhibition by drugs such as disulfiram (aldehyde dehydrogenase inhibitor)