Micro-RNA-21 regulates the sensitivity to cisplatin in human neuroblastoma cells.
OBJECTIVE
Drug resistance often causes treatment failure in neuroblastomas. Increasing evidence has implicated that the micro-RNAs (miRNAs) are involved in the development of drug resistance. In this report, we aimed to investigate the role of miRNA in cisplatin resistance of neuroblastoma cells.


METHODS
The cell viability of the neuroblastoma cells after cisplatin treatment was analyzed. The expression of the miRNAs and phosphatase and tensin homolog (PTEN) messenger RNA in the neuroblastoma cells was studied by real-time polymerase chain reaction. Overexpression of miRNA or suppression of miRNA expression by antagomir was used to investigate the effects of miRNA on the cisplatin-induced cell death or proliferation.


RESULTS
The expression of miR-21 was increased in the cisplatin-resistant (CisR) neuroblastoma cells as compared with the parental cells, and the antagomir against miR-21 converted the resistant cells into sensitive ones. Ectopic expression of pre-miR-21 in parental cells resulted in decreased sensitivity to cisplatin treatment. In addition, overexpression of pre-miR-21 markedly increa sed the proliferation rate of neuroblastoma cells. The level of PTEN messenger RNA and protein in the CisR cells was lower than that in the parental cells. Transfection of pre-miR-21 into the parental cells reduced the PTEN expression, and transfection of anti-miR-21 into the CisR cells increased the PTEN expression.


CONCLUSIONS
Micro-RNA-21 regulated the drug resistance and proliferation in neuroblastoma cells.
Department of Surgery, Far Eastern Memorial Hospital, Pan-Chiao, New Taipei, Taiwan.
Yun
Y
Chen
Ya-Hui
YH
Tsai
Yu
Y
Fang
Sheng-Hong
SH
Tseng
D000970:Antineoplastic Agents / Q000627:therapeutic use*; D002945:Cisplatin / Q000627:therapeutic use*; D019008:Drug Resistance, Neoplasm / Q000235:genetics*; D006801:Humans; D035683:MicroRNAs / Q000502:physiology*; D009447:Neuroblastoma / Q000188:drug therapy* / Q000235:genetics*; D014407:Tumor Cells, Cultured
D000970:Antineoplastic Agents; D035683:MicroRNAs; D002945:Cisplatin