[RbAp46 gene activates the expression of IGFBP-rP1 gene in K562 leukemic cells].
OBJECTIVE
To explore the mechanism of action of RbAp46 gene on leukemic cells.


METHODS
K562 leukemic cells and SHG44 glioma cells were transfected with eukaryotic expression vector carrying full-length cDNA of RbAp46 driven by the cytomegalovirus promoter mediated by lipofectamine transfection reagent. Empty vector were transfected at the same time as control. G418-resistant colonies were selected after 3 weeks culturing. Series genes were amplified using RT-PCR. Growth curve and colony formation assays were performed.


RESULTS
The number of K562/RbAp46 and K562/CMV cells were (90.00 +/- 8.40) x 10(4) and (119.58 +/- 9.87) x 10(4), respectively after 4 days growth, and SHG44/RbAp46 and SHG44/CMV cells were (89.13 +/- 4.88) x 10(4) and (149.42 +/- 10.83) x 10(4), respectively after 5 days growth. Seven-day yields of K562/RbAp46 and K562/CMV cell colonies were 131.67 +/- 15.57 and 250.33 +/- 26.31, respectively (P < 0.01), while those of SHG44/RbAp46 and SHG44/CMV cells were 50.78 +/- 6.77 and 206.67 +/- 37.18, respectively (P < 0.01). The fraction of K562/RbAp46 and K562/CMV cells in S phase was (48.88 +/- 4.35)% and (62.78 +/- 4.78)% (P < 0.01), and in G(0)/G(1) phase was (29.10 +/- 4.14)% and (22.40 +/- 2.43)%, respectively (P < 0.05), and that of SHG44/RbAp46 and SHG44/CMV cells in G(0)/G(1) phase was 65.6% and 48.8%, and in S phase was 22.6% and 38.4%, respectively. Insulin-like growth factor binding protein-related protein-1 (IGFBP-rP1) gene was induced to express only in the RbAp46-over expressing K562 cells and was not in SHG44 cells.


CONCLUSIONS
A regulatory pathway between RbAp46 and IGFBP-rP1 genes might exit in K562 leukemic cells.
Hu
Shao-yan
SY
Jiangsu Institute of Hematology, the First Affiliated Hospital of Soochow University, Suzhou 215006, China.
Chen
Zi-xing
ZX
Cen
Jian-nong
JN
Gu
Min
M
Zhao
Ye
Y
Shen
Hui-ling
HL
Wang
Wei
W
D002352:Carrier Proteins / Q000235:genetics*; D015972:Gene Expression Regulation, Neoplastic; D005822:Genetic Vectors; D006801:Humans; D018969:Insulin-Like Growth Factor Binding Proteins / Q000235:genetics*; D020014:K562 Cells; D009687:Nuclear Proteins / Q000235:genetics*; D056524:Retinoblastoma-Binding Protein 7; D014162:Transfection
D002352:Carrier Proteins; D018969:Insulin-Like Growth Factor Binding Proteins; D009687:Nuclear Proteins; C490746:RBBP7 protein, human; D056524:Retinoblastoma-Binding Protein 7; C102529:insulin-like growth factor binding protein-related protein 1