Proliferating Cell Nuclear Antigen: A Novel Growth and Therapeutic Biomarker

Proliferating cell nuclear antigen is a marker of cell proliferation and genomic maintenance. The protein undergoes several post-translational modifications that expand its playground and amplify its functions. Ubiquitylation, sumoylation, acetylation, phosphorylation, and nitrosylation are some of the modifications that confer a plethora of protein interactions with the antigen. These interactions regulate abundant functions like DNA replication, DNA damage control, and cell cycle control. Due to the versatile functions of the antigen, it may serve as a marker or target for therapeutic intervention for various diseases. This protein can be used as a marker for studies done to validate growth in medical and dental fields. The growth and proliferation of cells is a necessary factor for cancer to progress, both at primary and metastatic sites. It was proposed that PCNA can aid in not only the identification but also as a therapeutic agent for the disease due to its role in cell proliferation and DNA damage control. This review expounds on the structure and functions of PCNA. It discusses how the interactions of the antigen with other proteins can be used to block or enhance the functions of the cell being commanded by the antigen.