Abstract p53 is one of the most important tumor suppressor genes. In approximately half of all human cancers, p53 is inactivated as a direct result of mutations in the p53 gene. Furthermore, mutation or deletion of p53 is related to poor prognosis and resistance to chemotherapy and radiation. The activation of p53 is induced by a variety of cell stresses, such as DNA damage, oncogene activation, spindle damage and hypoxia. Activated p53 transactivates a number of genes, many of which are involved in DNA repair, cell cycle arrest and apoptosis. In this study, we tried to identify novel p53 target genes by the combination of chromatin-immunoprecipitation, transcriptome analysis and a search of p53 binding motif in silico. We infected lung cancer cell, H1299 (p53 null) with adenovirus vectors expressing FLAG-tagged p53, p63g and p73b, and then performed chromatin-immunoprecipitation (ChIP) with FLAG antibody. The immunoprecipitated DNA was subjected to next-generation sequencing (ChIP-Seq). The short sequences generated by ChIP-Seq were aligned to the human genome sequence and peaks which indicate the binding of p53 family protein were detected by several algorithms. We also searched p53 binding motif, RRRCWWGYYY appeared inside genes and 10k base upstream from its transcription start site, and selected ChIP-Seq peaks of which genomic positions include p53 binding motif. Furthermore we analyzed mRNA expression of H1299 cells by cDNA microarray including several long intergenic non-coding RNAs (lincRNAs) and next-generation sequencing (RNA-Seq). We combined three categories of data, mRNA expression, ChIP-Seq peaks and p53 binding motif in silico. As a result, we found several genes which are upregulated by p53 family proteins and have ChIP-Seq peaks with p53 binding motif in promoter regions or gene bodies. These genes included not only well-known p53 target genes such as p21 and MDM2 but also novel candidate genes. In addition, ChIP-PCR and reporter assay confirmed the binding and responsiveness to p53. Thus, our approach identified several novel target genes induce by p53. We are now analyzing the role of these genes in p53 response pathway. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1171. doi:1538-7445.AM2012-1171