title: Differential effects of AKT1(p.E17K) expression on human mammary luminal epithelial and myoepithelial cells.
abstract: Recently, we identified a somatic mutation in AKT1, which results in a glutamic acid to lysine substitution (p.Glu17Lys or E17K). E17K mutations appear almost exclusively in breast cancers of luminal origin. Cellular models involving cell lines such as human mammary epithelial and MCF10 are model systems that upon transformation lead to rare forms of human breast cancer. Hence, we studied the effects of E17K using a clinically pertinent luminal cell line model while providing evidence to explain why E17K mutations do not occur in the mammary myoepithelium. Thus the purpose of our study was to perform a functional and differential proteomics study to assess the role of AKT1(E17K) in the development of breast cancer. We used a set of genetically matched nontumorigenic and tumorigenic mammary luminal and myoepithelial cells. We demonstrated that in myoepithelial cells, expression of E17K inhibited growth, migration, and protein synthesis compared with wild-type AKT1. In luminal cells, E17K enhanced cell survival and migration, possibly offering a selective advantage in this type of cell. However, antineoplastic effects of E17K in luminal cells, such as inhibition of growth and protein synthesis, may ultimately be associated with favorable prognosis. Our study illustrates the importance of cellular context in determining phenotypic effects of putative oncogenic mutations.
authors.affiliation: Integrated Cancer Genomics Division, Translational Genomics Research Institute, Phoenix, Arizona 85004, USA.
authors.forename: Bodour
authors.initials: B
authors.lastname: Salhia
authors.forename: Courtney
authors.initials: C
authors.lastname: Van Cott
authors.forename: Tony
authors.initials: T
authors.lastname: Tegeler
authors.forename: Ashoka
authors.initials: A
authors.lastname: Polpitiya
authors.forename: Rachelle A
authors.initials: RA
authors.lastname: Duquette
authors.forename: Molly
authors.initials: M
authors.lastname: Gale
authors.forename: Galen
authors.initials: G
authors.lastname: Hostteter
authors.forename: Konstantinos
authors.initials: K
authors.lastname: Petritis
authors.forename: John
authors.initials: J
authors.lastname: Carpten
mesh_terms: D015153:Blotting, Western; D002460:Cell Line; D002465:Cell Movement / Q000235:genetics / Q000502:physiology; D049109:Cell Proliferation; D002851:Chromatography, High Pressure Liquid; D004847:Epithelial Cells / Q000166:cytology* / Q000378:metabolism*; D005455:Fluorescent Antibody Technique; D006801:Humans; D007150:Immunohistochemistry; D042361:Mammary Glands, Human / Q000166:cytology* / Q000378:metabolism*; D040901:Proteomics; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism*
chemical_list: C494918:AKT1 protein, human; D051057:Proto-Oncogene Proteins c-akt