MiR-24 induces chemotherapy resistance and hypoxic advantage in breast cancer

Giuseppina Roscigno, Ilaria Puoti, Immacolata Giordano, Elvira Donnarumma, Valentina Russo, Alessandra Affinito, Assunta Adamo, Cristina Quintavalle, Matilde Todaro, Maria dM Vivanco, Gerolama Condorelli

Research output: Contribution to journalArticle

Abstract

Breast cancer remains one of the leading causes of cancer mortality among women. It has been proved that the onset of cancer depends on a very small pool of tumor cells with a phenotype similar to that of normal adult stem cells. Cancer stem cells (CSC) possess self-renewal and multilineage differentiation potential as well as a robust ability to sustain tumorigenesis. Evidence suggests that CSCs contribute to chemotherapy resistance and to survival under hypoxic conditions. Interestingly, hypoxia in turn regulates self-renewal in CSCs and these effects may be primarily mediated by hypoxic inducible factors (HIFs). Recently, microRNAs (miRNAs) have emerged as critical players in the maintenance of pluripotency and self-renewal in normal and cancer stem cells. Here, we demonstrate that miR-24 is upregulated in breast CSCs and that its overexpression increases the number of mammospheres and the expression of stem cell markers. MiR-24 also induces apoptosis resistance through the regulation of BimL expression. Moreover, we identify a new miR-24 target, FIH1, which promotes HIFα degradation: miR-24 increases under hypoxic conditions, causing downregulation of FIH1 and upregulation of HIF1α. In conclusion, miR-24 hampers chemotherapy-induced apoptosis in breast CSCs and increases cell resistance to hypoxic conditions through an FIH1-HIFα pathway.

Original languageEnglish
JournalOncotarget
DOIs
Publication statusE-pub ahead of print - Jan 3 2017

Keywords

  • Journal Article

Fingerprint Dive into the research topics of 'MiR-24 induces chemotherapy resistance and hypoxic advantage in breast cancer'. Together they form a unique fingerprint.

  • Cite this

    Roscigno, G., Puoti, I., Giordano, I., Donnarumma, E., Russo, V., Affinito, A., Adamo, A., Quintavalle, C., Todaro, M., Vivanco, M. DM., & Condorelli, G. (2017). MiR-24 induces chemotherapy resistance and hypoxic advantage in breast cancer. Oncotarget. https://doi.org/10.18632/oncotarget.14470