TTC7B (tetratricopeptide repeat domain 7B) is a critical regulatory component of the PI4KA signaling complex that controls phosphatidylinositol 4-phosphate synthesis at the plasma membrane. TTC7B functions as a central bridging protein that directly interacts with phosphatidylinositol 4-kinase alpha (PI4KA), EFR3B, and FAM126A to form a functional heterotrimer 1. The EFR3A/B lipidated proteins recruit this complex to the plasma membrane, where TTC7B plays a pivotal structural role—disease-linked mutations in TTC7B disrupt EFR3 binding and decrease PI4KA membrane recruitment 12. Beyond membrane recruitment, TTC7B participates in broader signaling networks: it regulates calcineurin-mediated phosphatase signaling at the PI4KA complex 3 and triggers the PI4KA-AKT1-RXRA-FTO axis to suppress colon cancer proliferation through altered RNA m6A methylation 4. Clinically, TTC7B dysregulation is associated with poor prognosis in multiple cancers, including head and neck squamous cell carcinoma and colorectal cancer, where altered TTC7B expression correlates with immune infiltration and ferroptosis pathways 5. In glioma, low TTC7B expression independently predicts reduced overall survival and influences chemotherapy response 6. TTC7B stabilization by GIPC1-mediated inhibition of TRIM21-dependent ubiquitination suppresses colorectal cancer progression 7.