PINX1 (PIN2/TRF1 interacting telomerase inhibitor 1) is a chromosome 8-localized telomerase inhibitor functioning as a tumor suppressor through multiple mechanisms. Structurally, PINX1 binds directly to telomerase subunits hTERT and hTR, repressing telomerase activity by associating with the assembled hTERT-hTR complex 1. Beyond telomerase inhibition, PINX1 regulates NF-κB transcription factor activity, with its N-terminal domain (amino acids 2-252) modulating NF-κB-dependent gene expression more effectively than its C-terminal telomerase-inhibitor domain 2. Functionally, PINX1 suppresses cancer progression through the NF-κB/MMP-9 pathway, inhibiting breast cancer invasion and metastasis 3. Clinically, reduced PINX1 expression correlates with poor overall survival and disease-free survival, lymphatic invasion, and advanced tumor-node-metastasis stage across multiple cancer types 4. In gastric carcinoma, loss of heterozygosity and histone H4 hypoacetylation at the PINX1 locus associate with reduced expression and elevated telomerase activity 5. PINX1 expression varies among cancer types, suggesting cancer-specific roles in tumorigenesis and progression 6, with emerging therapeutic potential targeting both its telomerase-inhibitory and NF-κB-regulatory functions 7.