ALDH3B2 is an aldehyde dehydrogenase that catalyzes the oxidation of medium- and long-chain fatty aldehydes to non-toxic carboxylic acids 1. The enzyme localizes specifically to lipid droplets via C-terminal tryptophan residues and lipid modifications, where it functions as a quality control mechanism by removing lipid-derived aldehydes generated during oxidative stress 1. ALDH3B2 exhibits broad substrate preferences resembling other ALDH3 family members and participates in lipid homeostasis and oxidative stress defense 2. In cancer progression, ALDH3B2 demonstrates context-dependent roles: it promotes cholangiocarcinoma proliferation and invasion by upregulating Integrin Beta 1 expression and enhancing EMT, serving as an independent prognostic factor 3. Similarly, in non-small cell lung cancer, ALDH3B2 overexpression correlates with malignancy and poor prognosis, promoting EMT through the ALDH3B2/RPSA/AKT-ERK axis 4. Despite containing a premature stop codon in its DNA sequence, full-length ALDH3B2 protein is expressed in human placenta through stop codon readthrough 5. Recent positive selection signatures suggest ALDH3B2 evolved in opposition to ALDH2 for alcohol metabolism in Han Chinese populations 6.