Human Dynactin-Associated Protein Transforms NIH3T3 Cells to Generate Highly Vascularized Tumors with Weak Cell-Cell Interaction.
Human dynactin-associated protein (dynAP) is a transmembrane protein that promotes AktSer473 phosphorylation. Here, we report the oncogenic properties of dynAP. In contrast to control NIH3T3 cells expressing LacZ (NIH3T3LacZ), NIH3T3dynAP cells vigorously formed foci in two-dimensional culture, colonies on soft agar, and spheroids in anchorage-deficient three-dimensional culture. NIH3T3dynAP cells injected into nude mice produced tumors with abundant blood vessels and weak cell-cell contacts. Expression of dynAP elevated the level of rictor (an essential subunit of mTORC2) and promoted phosphorylation of FOXO3aSer253. FOXO3a is a transcriptional factor that stimulates expression of pro-apoptotic genes and phosphorylation of FOXO3a abrogates its function, resulting in promoted cell survival. Knockdown of rictor in NIH3T3dynAP cells reduced AktSer473 phosphorylation and formation of foci, colony in soft agar and spheroid, indicating that dynAP-induced activation of the mTORC2/AktSer473 pathway for cell survival contributes to cell transformation. E-cadherin and its mRNA were markedly reduced upon expression of dynAP, giving rise to cells with higher motility, which may be responsible for the weak cell-cell adhesion in tumors. Thus, dynAP could be a new oncoprotein and a target for cancer therapy.
Graduate School of Bioscience, Nagahama Institute of Bio-Science and Technology, Nagahama, Shiga, Japan.
Tatsuki
T
Kunoh
Graduate School of Bioscience, Nagahama Institute of Bio-Science and Technology, Nagahama, Shiga, Japan.
Weixiang
W
Wang
Graduate School of Bioscience, Nagahama Institute of Bio-Science and Technology, Nagahama, Shiga, Japan.
Hiroaki
H
Kobayashi
Graduate School of Bioscience, Nagahama Institute of Bio-Science and Technology, Nagahama, Shiga, Japan.
Daisuke
D
Matsuzaki
Graduate School of Bioscience, Nagahama Institute of Bio-Science and Technology, Nagahama, Shiga, Japan.
Yuki
Y
Togo
Graduate School of Bioscience, Nagahama Institute of Bio-Science and Technology, Nagahama, Shiga, Japan.
Masahiro
M
Tokuyama
Graduate School of Bioscience, Nagahama Institute of Bio-Science and Technology, Nagahama, Shiga, Japan.
Miho
M
Hosoi
Graduate School of Bioscience, Nagahama Institute of Bio-Science and Technology, Nagahama, Shiga, Japan.
Koichi
K
Koseki
Graduate School of Bioscience, Nagahama Institute of Bio-Science and Technology, Nagahama, Shiga, Japan.
Shu-Ichi
S
Wada
Graduate School of Bioscience, Nagahama Institute of Bio-Science and Technology, Nagahama, Shiga, Japan.
Nobuo
N
Nagai
Graduate School of Bioscience, Nagahama Institute of Bio-Science and Technology, Nagahama, Shiga, Japan.
Toshinobu
T
Nakamura
Graduate School of Bioscience, Nagahama Institute of Bio-Science and Technology, Nagahama, Shiga, Japan.
Shintaro
S
Nomura
Graduate School of Bioscience, Nagahama Institute of Bio-Science and Technology, Nagahama, Shiga, Japan.
Makoto
M
Hasegawa
Graduate School of Bioscience, Nagahama Institute of Bio-Science and Technology, Nagahama, Shiga, Japan; Frontier Pharma, Nagahama, Shiga, Japan.
Ryuzo
R
Sasaki
Graduate School of Bioscience, Nagahama Institute of Bio-Science and Technology, Nagahama, Shiga, Japan; Frontier Pharma, Nagahama, Shiga, Japan.
Tamio
T
Mizukami
D000818:Animals; D002450:Cell Communication; D002471:Cell Transformation, Neoplastic; D000072159:Dynactin Complex; D005260:Female; D006801:Humans; D007763:Lac Operon / Q000235:genetics; D051379:Mice; D008869:Microtubule-Associated Proteins / Q000235:genetics*; D041681:NIH 3T3 Cells; D009369:Neoplasms / Q000098:blood supply* / Q000235:genetics / Q000473:pathology*; D009389:Neovascularization, Pathologic / Q000235:genetics*; D015854:Up-Regulation
D000072159:Dynactin Complex; D008869:Microtubule-Associated Proteins