[Effects of transfected pIRES-p21(waf1)-p27(kip1) gene on the duplication of centrosomes and the proliferation of breast cancer cell line MCF-7].
OBJECTIVE
To explore the role of transfected pIRES-p21(waf1)-p27(kip1) gene on the centrosome duplication and cell proliferation of MCF-7, a breast cancer cell line.


METHODS
The pIRES-p21(waf1), pIRES-p27(kip1) and pIRES-p21(waf1)-p27(kip1) genes were transfected into the MCF-7 cells by lipofection. The effect on proliferation was evaluated by MTT assay and cell growth curve was drawn. The cell cycle was analyzed by flow cytometry. The centrosome duplication was detected by using indirect immunofluorescence microscopy.


RESULTS
After transfected 24 hours, the p21(waf1) and p27(kip1) protein expressions were significantly increased as compared with untransfected MCF-7 cells (P < 0.01), and cell growth was obviously inhibited and resulted in an accumulation of cells in G(1) (P < 0.01), presenting that the proportion of cells in G(1) phase was obviously increased from(47.28 +/- 2.25)% to (69.52 +/- 3.21)% of p21(waf1) transfected cells, (60.83 +/- 3.02)% of p27(kip1) transfected cells, and (78.37 +/- 2.83)% of p21 (waf1)-p27(kip1) transfected cells. The proportion of cells which contained unnormal centrosomes was obviously decreased, from (13.47 +/- 0.33)% to (5.07 +/- 0.38)%, (6.28 +/- 0.35)%, (3.47 +/- 0.23)%, respectively.


CONCLUSIONS
The transfer of p21(waf1) and p27(kip1) genes could inhibit the growth of human breast carcinoma cells and the unnormal duplication of centrosomes. p21(waf1) had a really synergy with p27(kip1) in these effects, suggesting p21(waf1)-p27(kip1) combined gene can inhibit the genesis and development of breast cancer and might have potential clinical significance as therapeutic agents of breast cancer.
Jiang
Dan-dan
DD
Department of Breast Surgary, the Affiliated Hospital of Qingdao Medical College, Qingdao 266003, China.
Li
Fu-nian
FN
Liu
Xiang-ping
XP
D001943:Breast Neoplasms / Q000235:genetics* / Q000473:pathology; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D018385:Centrosome / Q000378:metabolism*; D050759:Cyclin-Dependent Kinase Inhibitor p21 / Q000235:genetics*; D050760:Cyclin-Dependent Kinase Inhibitor p27; D005260:Female; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000235:genetics*; D014162:Transfection
C493956:CDKN1A protein, human; C436291:CDKN1B protein, human; D050759:Cyclin-Dependent Kinase Inhibitor p21; D047908:Intracellular Signaling Peptides and Proteins; D050760:Cyclin-Dependent Kinase Inhibitor p27