Based on limited published evidence, SMIM45 encodes small integral membrane proteins involved in neuron maturation according to UniProt annotations. The gene contains two open reading frames with distinct evolutionary origins: a conserved 68-amino acid sequence traceable to early vertebrate evolution, and a human-specific 107-amino acid peptide (SMIM45-107aa) that emerged during primate evolution 1. Recent studies show SMIM45-107aa is highly expressed in hepatocellular carcinoma tissues and promotes HCC progression through MTDH-MGST1-pAKT pathway interactions 2. A derived peptide inhibitor demonstrates anticancer potential, suggesting therapeutic applications.