MORN3 (MORN repeat containing 3) is a cancer-testis antigen that functions as a molecular adaptor assembling a suppression complex (suppresome) to regulate p53 tumor suppressor activity 1. Its primary mechanism involves recruiting post-translational modification (PTM) enzymes—specifically sirtuin deacetylase (SIRT1) and ubiquitin ligase (MDM2)—to confer composite modifications on p53 1. This dual-modification strategy promotes both deacetylation-mediated functional inactivation and ubiquitination-dependent degradation of p53, thereby enhancing proliferative and cell survival behaviors 1. The therapeutic relevance of MORN3 is evidenced by successful targeting with a rationally designed peptide (Morncide) that suppresses tumor growth through p53 reactivation 1. Clinically, MORN3 shows potential as a diagnostic biomarker for latent tuberculosis infection (LTBI), with elevated expression levels detected in LTBI patients compared to active tuberculosis cases 2. Additionally, MORN3 was identified among candidate genes in 12q24.31 microdeletion syndrome associated with intellectual disability and neuropsychiatric features 3. These findings position MORN3 as both an oncologically relevant target and a potential biomarker for infectious disease diagnosis.