Varying Detection of PCNA in Solid Tumor Cells: Effects of Fixation and Detergent

AbstractPCNA was immunohistochernically detected with a monoclonal antibody to PCNA in both formalin fixed-paraffin embedded and frozen sections of tissue specimens from human solid tumors. The percent of PCNA positive cells (PCNA score), extremely high in formalin fixed, paraffin embedded tissue sections, was decreased in frozen sections from the same tumor. The treatment of frozen sections with Triton X-100 further diminished the PCNA score as compared with that of frozen sections without such a treatment. These results suggest that there are at least 3 subpopulations of PCNA within human solid tumor cells. (The J Histotechnol 18:31, 1995)