Aryl-hydrocarbon receptor-dependent alteration of FAK/RhoA in the inhibition of HUVEC motility by 3-methylcholanthrene.
We previously demonstrated the antiproliferative and antiangiogenic effects of 3-methylcholanthrene (3MC), an aryl-hydrocarbon receptor (AhR) agonist, in human umbilical vascular endothelial cells (HUVECs). Herein, we unraveled its molecular mechanisms in inhibiting HUVEC motility. 3MC down-regulated FAK, but up-regulated RhoA, which was rescued by AhR knockdown. It led us to identify novel AhR binding sites in the FAK/RhoA promoters. Additionally, 3MC increased RhoA activity via suppression of a negative feedback pathway of FAK/p190RhoGAP. With an increase in membrane-bound RhoA, subsequent stress fiber and focal adhesion complex formation was observed in 3MC-treated cells, and this was reversed by a RhoA inhibitor and AhR antagonists. Notably, these compounds significantly reversed 3MC-mediated anti-migration in a transwell assay. The in vitro findings were further confirmed using an animal model of Matrigel formation in Balb/c mice. Collectively, AhR's genomic regulation of FAK/RhoA, together with RhoA activation, is ascribable to the anti-migration effect of 3MC in HUVECs.
Chang
Chih-Cheng
CC
Department of Physiology, Graduate Institute of Medical Sciences, Taipei Medical University, 250 Wu-Hsing Street, Taipei, 110, Taiwan.
Tsai
Shih-Ying
SY
Lin
Heng
H
Li
Hsiao-Fen
HF
Lee
Yi-Hsuan
YH
Chou
Ying
Y
Jen
Chih-Yu
CY
Juan
Shu-Hui
SH
D000818:Animals; D001665:Binding Sites; D002465:Cell Movement / Q000187:drug effects* / Q000502:physiology; D002478:Cells, Cultured; D047369:Chromatin Immunoprecipitation; D042783:Endothelial Cells / Q000166:cytology / Q000187:drug effects / Q000201:enzymology; D004730:Endothelium, Vascular / Q000166:cytology / Q000187:drug effects* / Q000201:enzymology; D025461:Feedback, Physiological; D051417:Focal Adhesion Kinase 1 / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D005786:Gene Expression Regulation; D006801:Humans; D008748:Methylcholanthrene / Q000494:pharmacology; D051379:Mice; D008807:Mice, Inbred BALB C; D011401:Promoter Regions, Genetic; D034622:RNA Interference; D012333:RNA, Messenger / Q000378:metabolism; D034741:RNA, Small Interfering; D018336:Receptors, Aryl Hydrocarbon / Q000819:agonists* / Q000037:antagonists & inhibitors / Q000502:physiology; D014470:Umbilical Cord / Q000166:cytology; D020742:rhoA GTP-Binding Protein / Q000235:genetics / Q000378:metabolism / Q000502:physiology*
D012333:RNA, Messenger; D034741:RNA, Small Interfering; D018336:Receptors, Aryl Hydrocarbon; D008748:Methylcholanthrene; D051417:Focal Adhesion Kinase 1; C496050:PTK2 protein, human; D020742:rhoA GTP-Binding Protein