H2O2 inhibits proliferation and mediates suppression of migration via DLC1/RhoA signaling in cancer cells.
BACKGROUND
RhoGTPase-activating proteins (RhoGAPs) regulate RhoGTPases in cells, but whether individual reactive oxygen species (ROS) regulate RhoGAPs is unknown. Our previous published papers have shown that deleted in liver cancer 1 (DLC1) inhibits cancer cell migration by its RhoGAP activity. The present study was designed to explore the role of H2O2 in regulation of DLC1.


METHODS
We treated cells with H2O2 for 24h and phenotypic changes were analyzed by MTT, RT-PCR, Western blotting, immunofluorescence staining and wound healing assays.


RESULTS
H2O2 downregulated cyclin D1 and cyclin E to inhibit proliferation, and upregulated BAX to induce apoptosis in MCF-7 cells. Compared with non-tumorigenic cells, H2O2 increased expression of DLC1 and reduced activity of RhoA in cancer cells. Stress fiber production and migration were also suppressed by H2O2 in MDA-MB-231 cells.


CONCLUSIONS
Our study suggests that H2O2 inhibits proliferation through modulation of cell cycle and apoptosis-related genes, and inhibits migration by decreasing stress fibers via DLC1/RhoA signaling.
Shandong Provincial Key Laboratory of Animal Resistant Biology, School of Life Sciences, Shandong Normal University, Jinan, China E-mail : grli@sdnu.edu.cn.
Long
L
Ma
Wen-Zhen
WZ
Zhu
Ting-Ting
TT
Liu
Hui-Ling
HL
Fu
Zhao-Jun
ZJ
Liu
Bing-Wu
BW
Yang
Tai-Yu
TY
Song
Guo-Rong
GR
Li
D017209:Apoptosis / Q000187:drug effects; D015153:Blotting, Western; D001940:Breast / Q000378:metabolism / Q000473:pathology; D001943:Breast Neoplasms / Q000378:metabolism / Q000473:pathology / Q000517:prevention & control*; D002453:Cell Cycle / Q000187:drug effects; D002465:Cell Movement / Q000187:drug effects*; D049109:Cell Proliferation / Q000187:drug effects*; D002478:Cells, Cultured; D005260:Female; D005455:Fluorescent Antibody Technique; D020690:GTPase-Activating Proteins / Q000235:genetics / Q000378:metabolism*; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects*; D006801:Humans; D006861:Hydrogen Peroxide / Q000494:pharmacology*; D008175:Lung Neoplasms / Q000378:metabolism / Q000473:pathology / Q000517:prevention & control*; D016877:Oxidants / Q000494:pharmacology; D012333:RNA, Messenger / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D025521:Tumor Suppressor Proteins / Q000235:genetics / Q000378:metabolism*; D014945:Wound Healing / Q000187:drug effects; D020742:rhoA GTP-Binding Protein / Q000235:genetics / Q000378:metabolism*
C112352:DLC1 protein, human; D020690:GTPase-Activating Proteins; D016877:Oxidants; D012333:RNA, Messenger; D025521:Tumor Suppressor Proteins; D006861:Hydrogen Peroxide; D020742:rhoA GTP-Binding Protein