OCIAD2 (Ovarian Carcinoma Immunoreactive Antigen Domain 2) is a mitochondrial protein with dual roles in cellular metabolism and cancer progression. Functionally, OCIAD2 localizes to the mitochondrial inner membrane where it controls assembly of respiratory chain complex III 1 and maintains mitochondrial structure and integrity 2. Beyond bioenergetics, OCIAD2 regulates cell migration through STAT3 activation 3 and influences JAK-STAT signaling 4. Mechanistically, OCIAD2 promotes cancer cell survival by suppressing mitochondria-initiated apoptosis, reducing mitochondrial membrane potential and cytochrome c release 2. In pancreatic cancer, OCIAD2 activates AKT signaling to enhance glycolysis and the Warburg effect 5. TGFβ signaling induces OCIAD2 expression through a pathway involving SMAD2/3 and androgen receptor 6. Clinically, OCIAD2 overexpression correlates with poor prognosis across multiple malignancies including lung adenocarcinoma, glioblastoma, and pancreatic cancer 274. Promoter hypomethylation drives OCIAD2 upregulation in lung cancer 8. OCIAD2 knockdown suppresses cancer cell proliferation, migration, and invasion while promoting apoptosis 27, establishing OCIAD2 as a potential therapeutic target for cancer treatment.