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Inhibition of malignant phenotypes of human osteosarcoma cells by a gene silencer, a pyrrole-imidazole polyamide, which targets an E-box motif.

ABSTRACT: Gene amplification and/or overexpression of the transcription factor c-MYC, which binds to the E-box sequence (5'-CACGTG-3'), has been observed in many human tumors. In this study, we have designed 5 pyrrole-imidazole (PI) polyamides recognizing E-box, and found that, among them, Myc-6 significantly suppresses malignant phenotypes of human osteosarcoma MG63 cells both in vitro and in vivo. Intriguingly, knockdown of the putative Myc-6 target MALAT1 encoding long noncoding RNA remarkably impaired cell growth of MG63 cells. Collectively, our present findings strongly suggest that Myc-6 exerts its tumor-suppressive ability at least in part through the specific down-regulation of MALAT1.

SUBMITTER: Taniguchi M

PROVIDER: S-EPMC4048845 | biostudies-literature | 2014

REPOSITORIES: biostudies-literature

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Inhibition of malignant phenotypes of human osteosarcoma cells by a gene silencer, a pyrrole-imidazole polyamide, which targets an E-box motif.

Taniguchi Masashi M Fujiwara Kyoko K Nakai Yuji Y Ozaki Toshinori T Koshikawa Nobuko N Toshio Kojima K Kataba Motoaki M Oguni Asako A Matsuda Hiroyuki H Yoshida Yukihiro Y Tokuhashi Yasuaki Y Fukuda Noboru N Ueno Takahiro T Soma Masayoshi M Nagase Hiroki H

FEBS open bio 20140313

Gene amplification and/or overexpression of the transcription factor c-MYC, which binds to the E-box sequence (5'-CACGTG-3'), has been observed in many human tumors. In this study, we have designed 5 pyrrole-imidazole (PI) polyamides recognizing E-box, and found that, among them, Myc-6 significantly suppresses malignant phenotypes of human osteosarcoma MG63 cells both in vitro and in vivo. Intriguingly, knockdown of the putative Myc-6 target MALAT1 encoding long noncoding RNA remarkably impaired ...[more]

PMID: 24918046

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