Proteomic analysis of cell cycle arrest and differentiation induction caused by ATPR, a derivative of all-trans retinoic acid, in human gastric cancer SGC-7901 cells.
4-amino-2-trifluoromethyl-phenyl retinate (ATPR) was reported to potentially inhibit proliferation and induce differentiation activity in some tumor cells. In this study, a proteomics approach was used to investigate the possible mechanism by screening the differentially expressed protein profiles of SGC-7901 cells before and after ATPR-treatment in vitro.



Peptides digested from the total cellular proteins were analyzed by reverse phase LC-MS/MS followed by a label-free quantification analysis. The SEQUEST search engine was used to identify proteins and bioinformatics resources were used to investigate the involved pathways for the differentially expressed proteins.



Thirteen down-regulated proteins were identified in the ATPR-treated group. Bioinformatics analysis showed that the effects of ATPR on 14-3-3ε might potentially involve the PI3K-AKT-FOXO pathway and P27Kip1 expression. Western blot and RT-PCR analysis showed that ATPR could inhibit AKT phosphorylation, up-regulate the expression of FOXO1A and P27Kip1 at both the protein and mRNA levels, and down-regulate the cytoplasmic expression of cyclin E and CDK2. ATPR-induced G0/G1 phase arrest and differentiation can be ablated if the P27kip1 gene is silenced with sequence-specific siRNA or in 14-3-3ε overexpression of SGC-7901 cells.



ATPR might cause cell cycle arrest and differentiation in SGC-7901 cells by simultaneously inhibiting the phosphorylation of AKT and down-regulating 14-3-3ε. This change would then enhance the inhibition of cyclin E/CDK2 by up-regulating FOXO1A and P27Kip1. Our findings could be of value for finding new drug targets and for developing more effective differentiation inducer.
School of Pharmacy, Anhui Medical University, Hefei, China.
Quan
Q
Xia
Department of Pharmacy, the First Affiliated Hospital of Anhui Medical University, Hefei, China.
Yingli
Y
Zhao
School of Pharmacy, Anhui Medical University, Hefei, China.
Jiali
J
Wang
School of Pharmacy, Anhui Medical University, Hefei, China.
Wenhao
W
Qiao
School of Pharmacy, Anhui Medical University, Hefei, China.
Dongling
D
Zhang
Chromatography and Mass Spectrometry Lab Hefei National Laboratory for Physical Science at Microscale, University of Science and Technology of China, Hefei, China.
Hao
H
Yin
Department of Pharmacy, the First Affiliated Hospital of Anhui Medical University, Hefei, China.
Dujuan
D
Xu
School of Pharmacy, Anhui Medical University, Hefei, China.
Feihu
F
Chen
D048948:14-3-3 Proteins / Q000378:metabolism; D000970:Antineoplastic Agents / Q000494:pharmacology*; D059447:Cell Cycle Checkpoints / Q000187:drug effects*; D002454:Cell Differentiation / Q000187:drug effects*; D045744:Cell Line, Tumor; D051858:Forkhead Transcription Factors / Q000378:metabolism; D006801:Humans; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D018809:Proliferating Cell Nuclear Antigen / Q000378:metabolism; D040901:Proteomics; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D012176:Retinoids / Q000494:pharmacology*; D015398:Signal Transduction / Q000187:drug effects; D013274:Stomach Neoplasms / Q000473:pathology*
D048948:14-3-3 Proteins; C585745:4-amino-2-trifluoromethyl-phenyl retinate; D000970:Antineoplastic Agents; D051858:Forkhead Transcription Factors; D018809:Proliferating Cell Nuclear Antigen; D012176:Retinoids; C413374:p27 antigen; D019869:Phosphatidylinositol 3-Kinases; D051057:Proto-Oncogene Proteins c-akt
ATPR; Cell cycle arrest and differentiation; PI3K-AKT-FOXO-P27kip1 pathway; Proteomics analysis; SGC-7901 cells