CYTIP (cytohesin 1 interacting protein) is a cytoplasmic regulator of integrin-mediated cell adhesion and migration. It functions as a negative regulator of β2-integrin activity by binding to cytohesin-1 and modulating ARF activation 1, thereby controlling LFA-1 integrin activation and dendritic cell adhesion dynamics 2. CYTIP localizes to the cell cortex and cytosol where it modulates TCR signaling thresholds through IL-7-induced dephosphorylation and co-localization with cytohesin-1 and LFA-1 3. The protein undergoes proteasome-dependent degradation during dendritic cell maturation, regulated by SOCS-1 interaction and ubiquitination 2, and is also degraded by herpesviral infection 1. CYTIP expression is dysregulated in multiple disease contexts: hypomethylation of its promoter associates with improved response to anti-PD-1 immunotherapy in non-small cell lung cancer, outperforming PD-L1 as a predictive biomarker for progression-free and overall survival 4. CYTIP functions as a hub gene in immune dysfunction states and aneuploidy-related cancer progression 56. The protein shows evolutionary conservation, with functional complementation between human CYTIP and its C. elegans homolog GRAS-1 in meiotic chromosome 2 7, indicating fundamental roles in integrin regulation and immune cell function.