[Targeted blockage of RNA binding protein E2 by decoy RNA induces the granulocytic differentiation of K562 cells].
OBJECTIVE
To use a decoy RNA targeted blockage of the RNA binding protein E2 (hnRNP E2) resulting in the CCAAT/enhancer-binding protein alpha (C/EBP alpha) gene's abnormal translation and investigate its effect on the granulocytic differentiation of K562 cells and the probable molecular mechanism.


METHODS
The hnRNP E2 decoy RNA expression plasmid was constructed and transfected into K562 cells with cationic liposome, and stable expression cells were obtained by G418 selection. The changes of C/EBP alpha and granulocyte colony-stimulating factor receptor (G-CSFR) gene expression were detected by RT-PCR and Western blot. The morphologic changes were observed after Wright-Giemsa staining. The expression of granulocytic differentiation antigens CD13 and CD15 was studied by immunocytochemistry.


RESULTS
The stably expressed pG cells were obtained. Its C/EBP alpha mRNA level remained unchanged, while 42kD-C/EBP alpha protein expression was increased by (49.7 +/- 5.5)% (P < 0.05); and G-CSFR mRNA was increased by (42.1 +/- 3.6)% (P < .05), and its protein was increased by (37.4 +/- 6.2)% (P < 0.05) compared to that in the K562 control cells. The characteristics of polymorphonuclear neutrophils appeared in pG cells and CD13 and CD15 positive cell ratios were (18.7 +/- 2.5)% and (26.3 +/- 2.9)% respectively.


CONCLUSIONS
HnRNP E2 decoy RNA can induce granulocytic differentiation of K562 cells, and G-CSF promotes this effect. The mechanisms may be that decoy RNA specifically blocks hnRNP E2, hence regulates the translation of C/ EBP alpha mRNA, restores the expression of 42kD-C/EBP alpha, and then up-regulates the expression of G-CSFR gene.
Chen
Xin-Min
XM
Department of Clinical Hematology, Key Laboratory of Laboratory Medical Diagnostics of Education Ministry, Chongqing Medical University, Chongqing 400016, China.
Feng
Wen-Li
WL
Xu
Song-Xiao
SX
Zeng
Jian-Ming
JM
Zhao
Shi-Qiao
SQ
Luo
Hong-Wei
HW
Bai
Wei-Jun
WJ
Wang
Xiao-Zhong
XZ
Huang
Zong-Gan
ZG
D022763:CCAAT-Enhancer-Binding Protein-alpha / Q000235:genetics*; D002454:Cell Differentiation / Q000235:genetics; D005786:Gene Expression Regulation; D034441:Heterogeneous-Nuclear Ribonucleoproteins / Q000235:genetics*; D006801:Humans; D020014:K562 Cells; D012313:RNA / Q000235:genetics*; D014175:Translating
D022763:CCAAT-Enhancer-Binding Protein-alpha; D034441:Heterogeneous-Nuclear Ribonucleoproteins; D012313:RNA