title: von Willebrand factor type D domain mutant of SVS-1/SUSD2, vWD(m), induces apoptosis in HeLa cells.
abstract: SVS-1/SUSD2 is a novel gene, which inhibits growth and reverses tumorigenic phenotypes of cancer cells in vitro. Here we report identification of a mutant of SVS-1, designated SVS-1-vWD(m), in which conserved amino acids GLLG at positions 591-594 in von Willebrand factor type D (vWD) domain are replaced by AAAA. As observed by laser confocal microscope, intracellular localization of the mutant protein has changed such that both the N-terminus and the C-terminus of SVS-1-vWD(m) were localized in the inner surface of the plasma membrane, whereas the N-terminus of SVS-1 was localized in the outer surface of the plasma membrane. Additionally, SVS-1-vWD(m) was processed much less efficiently and in a slightly different manner. In in vitro studies, adenovirus-mediated transduction of the SVS-1-vWD(m)gene induced growth suppression of HeLa cells in a dose-dependent manner, as the wild-type gene and inhibition of anchorage-independent growth. Of great interest is the finding that the mutant protein, vWD(m), but not the wild-type one induced apoptosis, as observed by nuclear as well as DNA fragmentation. Activation of caspase-3 and -9, but not caspase-8 or -12, was also demonstrated in vWD(m)-expressing cells. An inhibition of Akt phosphorylation, a major survival signaling component, also occurred in vWD(m)-expressing HeLa cells. Together these data suggest that vWD(m) induces apoptosis by inactivation of survival signaling component Akt and activation of caspase cascade (mitochondrial pathway) in HeLa cells. We propose SVS-1-vWD(m)as an alternative gene for use in developing new therapeutic strategies for the treatment of cancer.
authors.affiliation: Department of Bioinformatics, Soka University, Tokyo, Japan.
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Sugahara
authors.forename: Yzumi
authors.initials: Y
authors.lastname: Yamashita
authors.forename: Masahito
authors.initials: M
authors.lastname: Shinomi
authors.forename: Yumiko
authors.initials: Y
authors.lastname: Isobe
authors.forename: Banri
authors.initials: B
authors.lastname: Yamanoha
authors.forename: Hiroyoshi
authors.initials: H
authors.lastname: Iseki
authors.forename: Akihiko
authors.initials: A
authors.lastname: Takeda
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Okazaki
authors.forename: Kenji
authors.initials: K
authors.lastname: Kawai
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Suemizu
authors.forename: Toshiwo
authors.initials: T
authors.lastname: Andoh
mesh_terms: D017209:Apoptosis / Q000187:drug effects*; D053148:Caspase 3 / Q000378:metabolism; D053453:Caspase 9 / Q000378:metabolism; D049109:Cell Proliferation / Q000187:drug effects; D006367:HeLa Cells; D006801:Humans; D008562:Membrane Glycoproteins / Q000235:genetics; D008565:Membrane Proteins / Q000235:genetics / Q000494:pharmacology; D050505:Mutant Proteins / Q000494:pharmacology; D051058:Oncogene Protein v-akt / Q000187:drug effects; D017434:Protein Structure, Tertiary; D014841:von Willebrand Factor / Q000737:chemistry* / Q000235:genetics
chemical_list: D008562:Membrane Glycoproteins; D008565:Membrane Proteins; D050505:Mutant Proteins; C521511:SVS-1 protein, mouse; D014841:von Willebrand Factor; D051058:Oncogene Protein v-akt; D053148:Caspase 3; D053453:Caspase 9