Figure 7.

AATF is amplified in human tumours and displays a nuclear localization pattern in p53-proficient tumours. (A) Nuclear localization of AATF is selected for in p53-proficient tumours. Human endometrial tumours were stained for p53, AATF and MK2. p53-defective tumours show predominantly cytosolic AATF and nuclear MK2 staining (A—right) whereas tumours containing wild-type p53 display prominent nuclear enrichment of AATF accompanied by a prominent cytoplasmic MK2 signal (A—left). (B) Quantification of nuclear and cytoplasmic AATF staining was performed using a four-tier scoring system and subjected to statistical analysis (Fisher’s exact test). (C) AATF amplification is associated with increased resistance of lung cancer cell lines against cisplatin. Copy-number alterations as determined by SNP-arrays (blue=deletion; white=copy number neutral; red=amplification) at chromosome 17 (y axis) across all NSCLC cell lines are depicted (x axis). The chromosomal position of the amplification of AATF is highlighted for the analysed cell lines (zoom-in panel). HCC515 and Calu3 cells with copy number>4, H522 and A549 cells with copy number<4. (D) HCC515 (p53 mutant, AATF amplified), Calu3 (p53 wild type, AATF amplified), H522 (p53 mutant) and A549 (p53 wild type) cells were left untreated or exposed to cisplatin (10 μM) and harvested for FACS-based quantification of apoptosis using a cl.-caspase-3 antibody 24 h later. Asterisk indicates statistical significance, error bars represent s.d., n=12.