PARP2 and cancer: ASA-A, ASA-B and POPA brought about a considerably higher increase of the PARP2/ACTB mRNA ratio in the BRCA1-null UWB1.289 than in the BRCA1 wild-type UWB1.289 + BRCA1 cancer cells, with the ASA-B begetting a 140- to150-fold increase of the PARP2/ACTB mRNA ratio in UWB1.289 cells.