ABSTRACT: We determined the effect of p53 activation on de novo protein synthesis using quantitative proteomics of newly synthesized proteins (pulsed stable isotope labeling with amino acids in cell culture, pSILAC) in combination with mRNA and non-coding RNA expression analyses by next generation sequencing (RNA-, miR-Seq) in the colorectal cancer (CRC) cell line SW480. Furthermore, genome-wide DNA binding of p53 was analyzed by chromatin-immunoprecipitation (ChIP-Seq). Thereby, we identified differentially regulated mRNAs (1258 up, 415 down), miRNAs (111 up, 95 down), lncRNAs (270 up, 123 down) and proteins (542 up, 569 down). Changes in mRNA and protein expression levels showed a positive correlation (r = 0.50, p < 0.0001). More transcriptionally induced genes displayed occupied p53 binding sites (4.3% mRNAs, 7.2% miRNAs, 6.3% lncRNAs, 5.9% proteins) than repressed genes (2.4% mRNAs, 3.2% miRNAs, 0.8% lncRNAs, 1.9% proteins), suggesting indirect mechanisms of repression. Around 50% of the downregulated proteins displayed seed-matching sequences of p53-induced miRNAs in the corresponding 3â??-UTRs. Moreover, proteins repressed by p53 significantly overlapped with those previously shown to be repressed by miR-34a. We confirmed upregulation of the novel direct p53 target genes LINC01021, MDFI, ST14 and miR-486 and showed that ectopic LINC01021 expression inhibited proliferation in SW480 cells. Furthermore, HMGB1, KLF12 and CIT mRNAs were confirmed as direct targets of the p53-induced miR-34a, miR-205 and miR-486-5p, respectively. In line with the loss of p53 function during tumor progression, elevated expression of HMGB1, KLF12 and CIT was detected in advanced stages of cancer. This study provides new insights and a comprehensive catalogue of p53-mediated regulations and p53 DNA binding in CRC cells.