Figure 1.

p53 genotype and protein expression in UM-SCC cell lines. (a) The p53 genotype of ten University of Michigan series head and neck squamous cell carcinoma (UM-SCC) cell lines was analyzed by two-directional sequencing of four to nine exons. (b) Immunohistochemistry for p53 was performed on the UM-SCC cell lines using anti-p53 monoclonal antibody (DO-1, clone), and the panels were segregated according to minimal or weaker staining pattern typical for wild-type p53 (upper panels, except UM-SCC 11B) and strong nuclear staining typical for mutant p53 status of cells (lower panels). The cells stained with the isotype control primary antibody as negative control are presented in the small pictures located at the lower right corner of each image. The pictures were taken at a magnification of 100×.