PDLIM4 (PDZ and LIM domain 4) is a cytoskeletal regulatory protein that modulates actin organization and cell migration through its PDZ and LIM domains 1. The protein functions as a molecular scaffold that influences multiple cellular processes, including cell cycle regulation and stress response. PDLIM4 stabilizes p21 protein by blocking its RNA degradation, leading to G2/M cell cycle arrest and reduced cell proliferation in a p53-independent manner 2. In gastric cancer, PDLIM4 promotes malignant progression and cisplatin resistance by competitively inhibiting STUB1-mediated HSP70 ubiquitination, thereby activating MAPK signaling pathways 3. The protein also serves as a target of the circular RNA circ0002360/miR-629-3p regulatory axis, promoting gastric cancer cell proliferation and migration while inhibiting oxidative stress 4. PDLIM4 genetic polymorphisms influence bone metabolism, with specific variants associated with increased osteoporotic fracture risk through effects on bone turnover markers 5. The gene is transcriptionally regulated by BRD4 and produces alternative transcripts, including variants lacking the LIM domain 6. These findings establish PDLIM4 as a multifunctional protein with significant roles in cancer progression, bone metabolism, and cellular homeostasis.