PCNA

Proliferating cell nuclear antigen (PCNA) is a circular trimeric protein associated with cell cycle, which can serve as an assisting factor of DNA polymerase δ to ensure the continuous synthesis of leading strands during DNA replication. Meanwhile, PCNA can play an important regulatory role in DNA repairing through post-translational modifications. The expression level of PCNA significantly increases in G1 phase and reaches its peak in S phase, and then decreases in G2 and M phases, Synchronized with DNA synthesis. Therefore, in clinical practice, PCNA has become a specific biomarker for detecting proliferation cells, which can directly reflect the proliferation activity of cancer cells in almost all tumors, such as liver cancer, lung cancer, stomach cancer, colorectal cancer, breast cancer, ovarian cancer, etc. Moreover, some research has found that PCNA is involved in the occurrence and development of various cancers, which is closely related to tumor infiltration and metastasis, making it become a crucial prognostic indicator for various malignant tumors.