Researchers have reported that PCNA in the glioma of adult patients showed PCNA as an independent prognostic indicator, and its increased expression correlated with decreased patient survival.58 Pediatric and adult metastatic or relapsed high-grade gliomas have a higher PCNA appearance.58,59 Its expression permits evaluation of the efficacy of cancer treatment in a CAM model.60 Here, PCNA is linked to central nervous system cancer.