title: The gastrin gene promoter is regulated by p73 isoforms in tumor cells.
abstract: p73, a new p53 family member, is a transcription factor that is increasingly recognized in cancer research as an important player in tumorigenesis as well as in chemotherapeutic drug sensitivity. Despite the substantial structural and functional similarities to p53, accumulating evidence suggests that p53 and p73 may differently regulate their transcriptional targets. In this study, we have investigated the role of p73 in regulation of the gastrin gene promoter. Gastrin is a peptide hormone and an important factor in determining the progression of a number of human malignancies. Our results show that p73 can bind to the gastrin promoter. This leads to transcriptional upregulation of gastrin mRNA. We also found that the levels of gastrin and p73 transcripts correlate in primary gastric tumors. Taken together, our results demonstrate a novel mechanism for regulation of gastrin gene transcription and support a concept that p53 and p73 may have different biological roles in tumors.
authors.affiliation: Department of Surgery, Vanderbilt-Ingram Cancer Center, Vanderbilt University Medical Center, Nashville, TN 37232, USA.
authors.forename: K
authors.initials: K
authors.lastname: Tomkova
authors.forename: W
authors.initials: W
authors.lastname: El-Rifai
authors.forename: A
authors.initials: A
authors.lastname: Vilgelm
authors.forename: M C
authors.initials: MC
authors.lastname: Kelly
authors.forename: T C
authors.initials: TC
authors.lastname: Wang
authors.forename: A I
authors.initials: AI
authors.lastname: Zaika
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D004268:DNA-Binding Proteins / Q000235:genetics / Q000502:physiology*; D005755:Gastrins / Q000096:biosynthesis* / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D008175:Lung Neoplasms / Q000235:genetics / Q000378:metabolism; D051379:Mice; D009687:Nuclear Proteins / Q000235:genetics / Q000502:physiology*; D011401:Promoter Regions, Genetic; D020033:Protein Isoforms / Q000235:genetics / Q000502:physiology; D012333:RNA, Messenger / Q000096:biosynthesis; D013274:Stomach Neoplasms / Q000235:genetics / Q000378:metabolism; D000072160:Tumor Protein p73; D025521:Tumor Suppressor Proteins / Q000235:genetics / Q000502:physiology*
chemical_list: D004268:DNA-Binding Proteins; D005755:Gastrins; D009687:Nuclear Proteins; D020033:Protein Isoforms; D012333:RNA, Messenger; C000606460:TP73 protein, human; C000606368:Trp73 protein, mouse; D000072160:Tumor Protein p73; D025521:Tumor Suppressor Proteins