Fig. 1

MTAP immunostaining and 9p21 copy number status. (A,B) show tumor areas with MTAP deficiency (intensity “0”, blue arrow) and normal tissue with positive MTAP staining as control (intensity “2”, green arrow). (a) and (b) show tumor cell nuclei with homozygous MTAP deletion without any green 9p21 signals and presence of orange chromosome 9 signals in the tumor cell nuclei and 9p21 and chromosome 9 signals in adjacent normal cell nuclei. (c) shows the comparison of MTAP immunostaining and 9p21 copy number status.