(A) Immunoblotting with DO-1 antibody. Lane 1, CEM positive control; lane 2, case no. 11 with no p53 mutation; lane 3, case no. 4 with a 27-bp intragenic deletion; lane 4, case no. 10 with a 35-bp deletion; lane 5, case no. 5 with a 5-bp deletion at exon 7 and p53 protein negative by immunocytochemistry. (B) Immunoblotting of whole cell lysates from cases no. 4 (lanes 1 and 5) and case no. 10 (lanes 2 and 4) with PAb 1801 and PAb 421 antibodies. Case no. 4 (lanes 1 and 5) showed a 53-kD band with both antibodies and no band is observed with any of the antibodies in case no. 10 (lanes 2 and 4). Lane 3 and 6 correspond to CEM-positive control. (C) Comparison of the predicted amino acid sequence of case no. 4 with the wild-type p53 protein sequence.