title: Loss of ATF3 promotes Akt activation and prostate cancer development in a Pten knockout mouse model.
abstract: Activating transcription factor 3 (ATF3) responds to diverse cellular stresses, and regulates oncogenic activities (for example, proliferation, survival and migration) through direct transcriptional regulation or protein-protein interactions. Although aberrant ATF3 expression is frequently found in human cancers, the role of ATF3 in tumorigenesis is poorly understood. Here, we demonstrate that ATF3 suppresses the development of prostate cancer induced by knockout of the tumor suppressor Pten in mouse prostates. Whereas the oncogenic stress elicited by Pten loss induced ATF3 expression in prostate epithelium, we found that ATF3 deficiency increased cell proliferation and promoted cell survival, leading to early onset of mouse prostatic intraepithelial neoplasia and the progression of prostate lesions to invasive adenocarcinoma. Importantly, the loss of ATF3 promoted activation of the oncogenic AKT signaling evidenced by high levels of phosphorylated AKT and S6 proteins in ATF3-null prostate lesions. In line with these in vivo results, knockdown of ATF3 expression in human prostate cancer cells by single guided RNA-mediated targeting activated AKT and increased matrix metalloproteinase-9 expression. Our results thus link ATF3 to the AKT signaling, and suggest that ATF3 is a tumor suppressor for the major subset of prostate cancers harboring dysfunctional Pten.
authors.affiliation: GRU Cancer Center, Georgia Regents University, Augusta, GA, USA.|Center for Cell Biology and Cancer Research, Albany Medical College, Albany, NY, USA.
authors.forename: Z
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Center for Cell Biology and Cancer Research, Albany Medical College, Albany, NY, USA.
authors.forename: D
authors.initials: D
authors.lastname: Xu
authors.affiliation: GRU Cancer Center, Georgia Regents University, Augusta, GA, USA.|Department of Pathology, Georgia Regents University, Augusta, GA, USA.
authors.forename: H-F
authors.initials: HF
authors.lastname: Ding
authors.affiliation: Department of Biostatistics & Epidemiology, Georgia Regents University, Augusta, GA, USA.
authors.forename: J
authors.initials: J
authors.lastname: Kim
authors.affiliation: Department of Radiation Oncology, School of Medicine, Case Western Reserve University, Cleveland, OH, USA.
authors.forename: J
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Department of Molecular and Cellular Biochemistry, Ohio State University, Columbus, OH, USA.
authors.forename: T
authors.initials: T
authors.lastname: Hai
authors.affiliation: GRU Cancer Center, Georgia Regents University, Augusta, GA, USA.|Center for Cell Biology and Cancer Research, Albany Medical College, Albany, NY, USA.|Department of Biochemistry and Molecular Biology, Georgia Regents University, Augusta, GA, USA.
authors.forename: C
authors.initials: C
authors.lastname: Yan
mesh_terms: D051700:Activating Transcription Factor 3 / Q000235:genetics / Q000502:physiology*; D000818:Animals; D045744:Cell Line, Tumor; D004195:Disease Models, Animal; D004789:Enzyme Activation; D008297:Male; D020778:Matrix Metalloproteinase 2 / Q000378:metabolism; D020780:Matrix Metalloproteinase 9 / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D016328:NF-kappa B / Q000378:metabolism; D051059:PTEN Phosphohydrolase / Q000235:genetics / Q000502:physiology*; D011471:Prostatic Neoplasms / Q000201:enzymology / Q000378:metabolism / Q000473:pathology*; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism*; D015398:Signal Transduction
chemical_list: D051700:Activating Transcription Factor 3; C103002:Atf3 protein, mouse; D016328:NF-kappa B; D051057:Proto-Oncogene Proteins c-akt; D051059:PTEN Phosphohydrolase; C487757:Pten protein, mouse; D020778:Matrix Metalloproteinase 2; D020780:Matrix Metalloproteinase 9