Unknown

Dataset Information

0

Progestin suppression of miR-29 potentiates dedifferentiation of breast cancer cells via KLF4.


ABSTRACT: The female hormone progesterone (P4) promotes the expansion of stem-like cancer cells in estrogen receptor (ER)- and progesterone receptor (PR)-positive breast tumors. The expanded tumor cells lose expression of ER and PR, express the tumor-initiating marker CD44, the progenitor marker cytokeratin 5 (CK5) and are more resistant to standard endocrine and chemotherapies. The mechanisms underlying this hormone-stimulated reprogramming have remained largely unknown. In the present study, we investigated the role of microRNAs in progestin-mediated expansion of this dedifferentiated tumor cell population. We demonstrate that P4 rapidly downregulates miR-29 family members, particularly in the CD44(+) cell population. Downregulation of miR-29 members potentiates the expansion of CK5(+) and CD44(+) cells in response to progestins, and results in increased stem-like properties in vitro and in vivo. We demonstrate that miR-29 directly targets Krüppel-like factor 4 (KLF4), a transcription factor required for the reprogramming of differentiated cells to pluripotent stem cells, and for the maintenance of breast cancer stem cells. These results reveal a novel mechanism, whereby progestins increase the stem cell-like population in hormone-responsive breast cancers, by decreasing miR-29 to augment PR-mediated upregulation of KLF4. Elucidating the mechanisms whereby hormones mediate the expansion of stem-like cells furthers our understanding of the progression of hormone-responsive breast cancers.

SUBMITTER: Cittelly DM 

PROVIDER: S-EPMC4236860 | BioStudies | 2013-01-01

REPOSITORIES: biostudies

Similar Datasets

2015-01-01 | S-EPMC4369481 | BioStudies
2012-01-01 | S-EPMC4158006 | BioStudies
2013-01-01 | S-EPMC3549640 | BioStudies
2008-01-01 | S-EPMC2311360 | BioStudies
2020-01-01 | S-EPMC7085458 | BioStudies
1000-01-01 | S-EPMC4800289 | BioStudies
2017-01-01 | S-EPMC5668194 | BioStudies
2012-01-01 | S-EPMC3287001 | BioStudies
2012-01-01 | S-EPMC4716679 | BioStudies
2015-01-01 | S-EPMC4741755 | BioStudies