TY - JOUR
T1 - TWIST1 heterodimerization with e12 requires coordinated protein phosphorylation to regulate periostin expression
AU - Mikheeva, Svetlana A.
AU - Camp, Nathan D.
AU - Huang, Lei
AU - Jain, Antrix
AU - Jung, Sung Yun
AU - Avci, Naze G.
AU - Tokita, Mari
AU - Wolf-Yadlin, Alejandro
AU - Zhang, Jing
AU - Tapscott, Stephen J.
AU - Rostomily, Robert C.
AU - Mikheev, Andrei M
N1 - Funding Information:
Funding: This research was funded by the National Institute of Health, grant nos. R01CA136808, R01NS091251 (to R.C.R), R21NS082542 (to A.M.M.), and P01CA077852.
Publisher Copyright:
© 2019 by the authors. Licensee MDPI, Basel, Switzerland. T.
PY - 2019/9
Y1 - 2019/9
N2 - Diffuse invasion into adjacent brain matter by glioblastoma (GBM) is largely responsible for their dismal prognosis. Previously, we showed that the TWIST1 (TW) bHLH transcription factor and its regulated gene periostin (POSTN) promote invasive phenotypes of GBM cells. Since TW functional effects are regulated by phosphorylation and dimerization, we investigated how phosphorylation of serine 68 in TW regulates TW dimerization, POSTN expression, and invasion in glioma cells. Compared with wild-type TW, the hypophosphorylation mutant, TW(S68A), impaired TW heterodimerization with the E12 bHLH transcription factor and cell invasion in vitro but had no effect on TW homodimerization. Overexpression of TW:E12 forced dimerization constructs (FDCs) increased glioma cell invasion and upregulated pro-invasive proteins, including POSTN, in concert with cytoskeletal reorganization. By contrast, TW:TW homodimer FDCs inhibited POSTN expression and cell invasion in vitro. Further, phosphorylation of analogous PXSP phosphorylation sites in TW:E12 FDCs (TW S68 and E12 S139) coordinately regulated POSTN and PDGFRa mRNA expression. These results suggested that TW regulates pro-invasive phenotypes in part through coordinated phosphorylation events in TW and E12 that promote heterodimer formation and regulate downstream targets. This new mechanistic understanding provides potential therapeutic strategies to inhibit TW-POSTN signaling in GBM and other cancers.
AB - Diffuse invasion into adjacent brain matter by glioblastoma (GBM) is largely responsible for their dismal prognosis. Previously, we showed that the TWIST1 (TW) bHLH transcription factor and its regulated gene periostin (POSTN) promote invasive phenotypes of GBM cells. Since TW functional effects are regulated by phosphorylation and dimerization, we investigated how phosphorylation of serine 68 in TW regulates TW dimerization, POSTN expression, and invasion in glioma cells. Compared with wild-type TW, the hypophosphorylation mutant, TW(S68A), impaired TW heterodimerization with the E12 bHLH transcription factor and cell invasion in vitro but had no effect on TW homodimerization. Overexpression of TW:E12 forced dimerization constructs (FDCs) increased glioma cell invasion and upregulated pro-invasive proteins, including POSTN, in concert with cytoskeletal reorganization. By contrast, TW:TW homodimer FDCs inhibited POSTN expression and cell invasion in vitro. Further, phosphorylation of analogous PXSP phosphorylation sites in TW:E12 FDCs (TW S68 and E12 S139) coordinately regulated POSTN and PDGFRa mRNA expression. These results suggested that TW regulates pro-invasive phenotypes in part through coordinated phosphorylation events in TW and E12 that promote heterodimer formation and regulate downstream targets. This new mechanistic understanding provides potential therapeutic strategies to inhibit TW-POSTN signaling in GBM and other cancers.
KW - Dimerization
KW - Glioblastoma
KW - Invasion
KW - Periostin
KW - TWIST1
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UR - http://www.scopus.com/inward/citedby.url?scp=85073472003&partnerID=8YFLogxK
U2 - 10.3390/cancers11091392
DO - 10.3390/cancers11091392
M3 - Article
AN - SCOPUS:85073472003
SN - 2072-6694
VL - 11
JO - Cancers
JF - Cancers
IS - 9
M1 - 1392
ER -