ADGB (androglobin) is a recently identified chimeric globin superfamily member containing a calpain domain and circularly permutated globin domain with a bis-histidyl hexacoordinated heme-iron atom 1. The protein binds dioxygen, carbon monoxide, and nitric oxide 1, and likely functions as a sensor for reactive oxygen and nitrogen species chemistry 2. ADGB expression is predominantly abundant in testis but also occurs in tissues with motile cilia, including the female reproductive tract, lungs, and brain 3. Its transcriptional regulation involves multiple mechanisms: FOXJ1 and RFX2 (key ciliogenesis transcription factors) substantially enhance ADGB promoter activity 3, while MYBL2 and RFX3 also regulate ADGB expression 45. Clinically, ADGB is essential for male fertility. ADGB variants cause asthenozoospermia through disrupted calmodulin binding, while Adgb-/- mice exhibit reduced sperm concentration and motility with malformed spermatids 6. ADGB interacts with proteins controlling sperm flagella formation and motility, including CFAP69 and SPEF2 6. In cancer contexts, while ADGB overexpression increases cell motility and extracellular matrix restructuring in vitro 5, ADGB is typically downregulated in lung, testis, and other human tumors, suggesting limited in vivo tumorigenic relevance 5.