TY - JOUR
T1 - Reduction in cyclin D1/Cdk4/retinoblastoma protein signaling by CRE-decoy oligonucleotide
AU - Park, Yun Gyu
AU - Park, Serkin
AU - Lim, Seoung Ok
AU - Lee, Moon Seop
AU - Ryu, Chong Kun
AU - Kim, Insun
AU - Cho-Chung, Yoon S.
N1 - Funding Information:
1This work was supported in part by grants from the Korea Research Foundation (2000-041-F00014) and Medical Science Research Center at Korea University (1999-203). 2To whom correspondence and reprint requests should be addressed at 126-1, 5-ga, Anam-dong, Sungbuk-gu, Seoul, 136-701, Korea. Fax: 82-2-923-0480. E-mail: parkyg@korea.ac.kr.
PY - 2001
Y1 - 2001
N2 - We have previously demonstrated that the activation of p53 signaling may contribute to tumor growth inhibition by the CRE-decoy oligonucleotide containing CRE sequence (5′-TGACGTCA-3′) (Lee et al., Biochemistry 39, 4863-4868, 2000). However, growth inhibition by CRE-decoy treatment was also observed in tumor cells containing a mutant p53 (Park et al., J. Biol. Chem. 274, 1573-1580, 1999). To understand additional mechanisms of the decoy oligonucleotide, we investigated the effect on cyclin D1 expression and a cyclin D1/Cdk4/retinoblastoma protein (pRB) signaling pathway. Here we show that in MCF7 breast cancer cells the CRE-decoy competed with cyclin D1-CRE (5′-TAACGTCA-3′) for binding transcription factors and reduced cyclin D1 gene expression (in reporter gene assay, Northern blotting and Western blotting) to modulate cyclin D1/Cdk4/pRB signaling and G1-S progression in a steady state and/or under estrogen stimulation. Decrease of cyclin D1 protein level by CRE-decoy treatment was also observed in p53-mutated cancer cells. Cyclin D1 expression was also diminished in MCF7 cells stably expressing dominant negative mutant CREB indicating that the nonspecific effect of oligonucleotide or its degradation products could be excluded. These data suggest that inhibition of cyclin D1 expression contributes to the growth inhibition induced by the decoy oligonucleotide in MCF7 cells through a cyclin D1/Cdk4/pRB signaling pathway. Downregulation of cyclin D1 expression also provides a mechanism of CRE-decoy-induced growth inhibition in tumor cells having p53 mutation.
AB - We have previously demonstrated that the activation of p53 signaling may contribute to tumor growth inhibition by the CRE-decoy oligonucleotide containing CRE sequence (5′-TGACGTCA-3′) (Lee et al., Biochemistry 39, 4863-4868, 2000). However, growth inhibition by CRE-decoy treatment was also observed in tumor cells containing a mutant p53 (Park et al., J. Biol. Chem. 274, 1573-1580, 1999). To understand additional mechanisms of the decoy oligonucleotide, we investigated the effect on cyclin D1 expression and a cyclin D1/Cdk4/retinoblastoma protein (pRB) signaling pathway. Here we show that in MCF7 breast cancer cells the CRE-decoy competed with cyclin D1-CRE (5′-TAACGTCA-3′) for binding transcription factors and reduced cyclin D1 gene expression (in reporter gene assay, Northern blotting and Western blotting) to modulate cyclin D1/Cdk4/pRB signaling and G1-S progression in a steady state and/or under estrogen stimulation. Decrease of cyclin D1 protein level by CRE-decoy treatment was also observed in p53-mutated cancer cells. Cyclin D1 expression was also diminished in MCF7 cells stably expressing dominant negative mutant CREB indicating that the nonspecific effect of oligonucleotide or its degradation products could be excluded. These data suggest that inhibition of cyclin D1 expression contributes to the growth inhibition induced by the decoy oligonucleotide in MCF7 cells through a cyclin D1/Cdk4/pRB signaling pathway. Downregulation of cyclin D1 expression also provides a mechanism of CRE-decoy-induced growth inhibition in tumor cells having p53 mutation.
KW - CRE-decoy oligonucleotide
KW - Cyclin D1
KW - G1 phase arrest
KW - Retinoblastoma protein
KW - Tumor growth inhibition
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U2 - 10.1006/bbrc.2001.4521
DO - 10.1006/bbrc.2001.4521
M3 - Article
C2 - 11243864
AN - SCOPUS:0034811055
VL - 281
SP - 1213
EP - 1219
JO - Biochemical and Biophysical Research Communications
JF - Biochemical and Biophysical Research Communications
SN - 0006-291X
IS - 5
ER -