The PAGE4 (P antigen family member 4) antibody is a tool used to detect the PAGE4 protein, a member of the cancer/testis antigen (CTA) family. CTAs are proteins typically expressed in germ cells (e.g., testes) but aberrantly re-expressed in various cancers. PAGE4. encoded by the *PAGE4* gene on the X chromosome, is notable for its restricted expression in normal tissues and frequent upregulation in malignancies, particularly prostate cancer. Its expression is associated with stress responses, cellular differentiation, and tumorigenesis, though its precise biological role remains under investigation.
Structurally, PAGE4 is an intrinsically disordered protein, allowing flexible interactions with binding partners like heat shock protein 70 (HSP70), which may influence stress-related signaling pathways. Studies suggest PAGE4 modulates transcriptional regulation, potentially impacting pathways such as Wnt/β-catenin in prostate cancer progression. The PAGE4 antibody is critical for research applications, including immunohistochemistry, Western blotting, and immunofluorescence, enabling localization and quantification of PAGE4 in cellular or tissue samples.
Clinically, PAGE4 has been explored as a diagnostic or prognostic biomarker due to its cancer-specific expression. Its overexpression in prostate tumors correlates with disease aggressiveness, making it a candidate for targeted therapies or immunotherapies. However, clinical utility remains preliminary, requiring further validation. The PAGE4 antibody thus serves as a key reagent in both mechanistic studies and translational research, bridging gaps between PAGE4's molecular functions and its potential therapeutic applications.