PCNA and neoplasm: We can also point out that in medulloblastoma samples in areas of the tumors with high staining of the neuronal differentiation marker β3tubulin, the staining of γtubulin is low, whereas in tumor areas with low staining of β3tubulin, there is a strong co-staining of γtubulin and the proliferative marker proliferating cell nuclear antigen (PCNA) further confirming that there is a connection between γtubulin expression and highly proliferative tumors [147].